Configuring Firewall Device Interfaces
The Interfaces page displays configured physical interfaces, logical interfaces, and redundant interfaces, as well as hardware ports and bridge groups, for the selected device. From this page, you can add, edit and delete interfaces; enable communication between interfaces on the same security level; and manage VPDN groups and PPPoE users.
Note
The Interfaces page displayed for ASA 5505 devices presents two tabbed panels: Hardware Ports and Interfaces. Similarly, the Interfaces page displayed for the Catalyst 6500 services modules (ASA-SMs and FWSMs) operating in transparent mode also presents two tabbed panels: Interfaces and Bridge Groups.
Navigation Path
To access the Interfaces page, select a security device in Device View and then select Interfaces from the Device Policy selector.
This section contains the following topics:
Understanding Device Interfaces
An interface is a point of connection between a security device and some other network device. Interfaces are initially disabled; thus, as an essential part of firewall configuration, interfaces must be enabled and configured to allow appropriate packet inspection and forwarding.
There are two types of interface: physical and logical, where a physical interface is the actual slot on the device into which a network cable is plugged, and a logical interface is a virtual port assigned to a specific physical port. Generally, physical ports are referred to as interfaces, while logical ports are referred to as subinterfaces, virtual interfaces, VLANs, or EtherChannels, depending on their function. The number and type of interfaces you can define varies with appliance model and type of license purchased.
Note
On devices running version 6.3 of the PIX operating system, the labels “physical” and “logical” are used, rather than “interface” and “subinterface.” Also, transparent mode and multiple contexts are not supported on these devices.
Subinterfaces let you divide a physical interface into multiple logical interfaces that are tagged with different VLAN IDs. Because VLANs keep traffic separate on a given physical interface, you can increase the number of interfaces available to your network without adding additional physical interfaces or security appliances. This feature is particularly useful in multiple-context mode, allowing you to assign unique interfaces to each context.
As a general rule, interfaces attach to router-based networks, and subinterfaces attach to switch-based networks. All subinterfaces must be associated with a physical interface that is responsible for routing allowed traffic correctly.
If you use subinterfaces, you typically do not also want the physical interface to pass traffic, because the physical interface passes untagged packets. The physical interface must be enabled for the subinterface to pass traffic, but do not name the physical interface to ensure it does not pass traffic. However, if you do want to let the physical interface pass untagged packets, you can name the interface as usual. See Managing Device Interfaces, Hardware Ports, and Bridge Groups for information about naming an interface.
Note
The ASA 5505, combining switch and security appliance features, is a special case in that you configure both physical switch ports and logical VLAN interfaces. See Understanding ASA 5505 Ports and Interfaces for more information.
The Catalyst 6500 services modules (ASA-SMs and FWSMs) do not include any external physical interfaces—instead, they use internal VLAN interfaces. For example, assume you assign VLAN 201 to an FWSM inside interface, and VLAN 200 to the outside interface. You assign these VLANs to physical switch ports, and hosts connect to those ports. When communication occurs between VLANs 201 and 200, the FWSM is the only available path between the VLANs, forcing traffic to be statefully inspected.
See the following sections for additional information about device interfaces:
Security Appliance Configurations
Firewall devices allow a variety of configurations, and the configuration determines how to define the interfaces associated with a specific device. The following table outlines the various configurations.
Table 46-1 Security Appliance Configurations
|
Operational Mode (Router or Transparent)
|
Context Support (Single or Multiple)
|
PIX 6.3.x |
N/A |
N/A |
PIX 7.0+/ASA |
Router or Transparent |
Single |
PIX 7.0+/ASA, or security context of unmanaged PIX 7.0+/ASA |
Router or Transparent |
Multiple (see Checklist for Configuring Multiple Security Contexts) |
FWSM, or security context of unmanaged switch (multiple mode) |
Router or Transparent |
Single or Multiple |
Interfaces in Routed and Transparent Modes
Beginning with ASA/PIX 7.0 and FWSM 2.2.1, you can configure a security device to operate in one of two modes: routed or transparent. (The PIX 6.3 operates only in routed mode.)
In routed mode, the security appliance acts as a gateway or router for connected networks: it maintains IP addresses for its interfaces, and inspects and filters traffic traversing these interfaces based on IP address (Layer 3) information. In this mode, each device interface is connected to a different IP subnet, and has its own IP address on that subnet. Routed mode supports up to 256 interfaces in single mode or per context, with a maximum of 1000 interfaces divided between all contexts.
In transparent mode, the security appliance operates as a Layer 2 (data link) device, or transparent bridge, and is often referred to as a “bump in the wire,” or a “stealth firewall.” In this mode, you can define only two interfaces: inside and outside. The interfaces do not require IP addresses; they use VLAN IDs to forward inspected traffic. However, if the device includes a dedicated management interface, you can use it—either the physical interface or a subinterface—as a third interface for device-management traffic.
Note
Cisco Security Manager does not populate the interface information for FWSM 2.x devices during discovery.
Bridge Groups
Beginning with the ASA 8.4.1 and FWSM 3.1, in transparent mode, you can increase the number of interfaces available to a device or context through use of bridge groups. You can configure up to eight bridge groups; on an FWSM each group can contain two interfaces; on an ASA 9.7.1 (Cisco Security Manager 4.13) each group can contain upto 64 interfaces. See Add/Edit Bridge Group Dialog Box for more information.
Related Topics
Interfaces in Single and Multiple Contexts
Security “contexts” allow a single physical device to operate as multiple, independent firewalls. In multiple-context mode, each context defines a single virtual firewall, complete with its own configuration. Each context acts as a unique virtual firewall that inspects and filters traffic traversing the interfaces allocated to that context. Each context is “unaware” of other contexts defined on the same security appliance.
As with a single-context, routed-mode device, interfaces on a multiple-context device connect to router-based networks, subinterfaces connect to switch-based networks, and each subinterface must be associated with an interface that routes allowed traffic correctly.
However, you cannot define IP addresses, the routed-mode portion of the configuration, or identify the management interface until you have defined and deployed the contexts. But you cannot define a security context until you have defined the necessary interfaces and subinterfaces.
In other words, you must enable and configure the interfaces and subinterfaces on a device that will provide multiple security contexts (in either routed or transparent mode) before you can define and configure the security contexts themselves.
Refer to Chapter 59, “Configuring Security Contexts on Firewall Devices” for more information.
About Asymmetric Routing Groups
In some situations, return traffic for a session may be routed through a different interface than the one from which it originated. Similarly, in failover configurations, return traffic for a connection that originated on one unit may return through the peer unit. This most commonly occurs when two interfaces on a single FWSM, or two FWSMs in a failover pair, are connected to different service providers and the outbound connection does not use a NAT address. By default, the FWSM drops the return traffic because there is no connection information for that traffic.
You can prevent return traffic being dropped by assigning the VLAN interfaces on which this is likely to occur to an asymmetric routing (ASR) group. When a member interface receives a packet for which it has no session information, it checks the session information for other interfaces that are members of the same group.
If a match is not found, the packet is dropped. If a match is found, one of the following actions occurs:
- If the incoming traffic originated on a different interface on the same FWSM, some or all of the Layer 2 header is rewritten and the packet is re-injected into the stream.
- If the incoming traffic originated on a peer unit in a failover configuration, some or all of the Layer 2 header is rewritten and the packet is redirected to the other unit. This redirection continues as long as the session is active.
Note
In failover configurations, you must enable Stateful Failover for session information to be passed from the standby unit or failover group to the active unit or failover group.
To assign an FWSM virtual interface to an asymmetric routing group, simply specify an ASR Group ID in the Add/Edit Interface Dialog Box: Advanced Tab (ASA/PIX 7.0+). If the group does not exist, it is created and the interface assigned to it.
You must repeat the assignment for each interface that will participate in this ASR group. You can create up to 32 ASR groups and assign a maximum of eight interfaces to each group.
Note
The upstream and downstream routers must use one MAC address per VLAN, and have different MAC addresses for different VLANs, to allow the redirection of packets from a standby unit to an active unit in failover configurations.
Understanding ASA 5505 Ports and Interfaces
The ASA 5505 is unique in that it includes a built-in switch, and there are two kinds of ports and interfaces that you need to configure:
- Physical switch ports – The ASA 5505 has eight Fast Ethernet switch ports that forward traffic at Layer 2, using the switching function in hardware. Two of these ports are power-over-Ethernet (PoE) ports. You can connect these ports directly to user equipment such as PCs, IP phones, or DSL modems. Or you can connect to another switch.
- Logical VLAN interfaces – In routed mode, these interfaces forward traffic between VLAN networks at Layer 3, using the configured security policy to apply firewall and VPN services. In transparent mode, these interfaces forward traffic between the VLANs on the same network at Layer 2, using the configured security policy to apply firewall services.
To segregate the switch ports into separate VLANs, you assign each switch port to a VLAN interface. Switch ports on the same VLAN can communicate with each other using hardware switching. But when a switch port on one VLAN attempts to communicate with a switch port on another VLAN, the ASA 5505 applies the security policy to the traffic, and routes or bridges between the two VLANs.
Note
Subinterfaces and redundant interfaces are not available on the ASA 5505.
Navigation Path
The Interfaces page displayed for ASA 5505 devices presents two tabbed panels: Hardware Ports and Interfaces. To access these panels, select an ASA 5505 in Device View and then select Interfaces from the Device Policy selector.
Configuring ASA 5505 Switch Ports and Interfaces
Refer to Configuring Hardware Ports on an ASA 5505 for information about configuring the switch ports.
Refer to Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM) for information about configuring the interfaces.
Related Topics
Configuring Subinterfaces (PIX/ASA)
Subinterfaces let you divide a physical interface into multiple logical interfaces that are tagged with different VLAN IDs. Because VLANs keep traffic separate on a given physical interface, you can increase the number of interfaces available to your network without adding additional physical interfaces or security appliances. This feature is particularly useful in multiple-context mode, letting you assign unique interfaces to each context.
Note
If you use subinterfaces, you typically do not also want the physical interface to pass traffic, as the physical interface passes untagged packets. Because the physical interface must be enabled for the subinterface to pass traffic, do not name the physical interface to ensure it does not pass traffic. However, if you do want to let the physical interface pass untagged packets, you can name the interface as usual.
Note
This option is available only on PIX 7.0+ and non-5505 ASA devices.
Defining Subinterfaces
Follow these steps to configure a subinterface in the Add/Edit Interface (ASA/PIX 7.0+) dialog box, which is accessed from the device Interfaces page (see Managing Device Interfaces, Hardware Ports, and Bridge Groups).
1.
Choose Subinterface as the interface Type in the Add/Edit Interface dialog box.
The VLAN ID and Subinterface ID fields appear below the Hardware Port, Name and Security Level fields.
2.
Choose the desired Hardware Port from the list of previously defined interface ports. If you do not see a desired interface ID, be sure that Interface is defined and enabled.
3.
VLAN ID – Provide a VLAN ID for this subinterface: enter a value between 1 and 4094. The specified VLAN ID must not be in use on any connected device.
Some VLAN IDs might be reserved on connected switches; see the switch documentation for more information. In multiple-context mode, you can only set the VLAN ID in the system configuration.
4.
Secondary VLAN ID – Provide a secondary VLAN ID value for this subinterface; this enables the ASA to map the packets that arrive on the ASA on the secondary VLAN to a primary VLAN. configure: Enter a value between 1 and 4090.
The secondary VLAN ID must be unique and not be the same as a VLAN ID. A secondary VLAN is supported on devices running ASA 9.5.2 or later in single context, in routed or firewall mode or as an L2 cluster.
Note
You can add multiple VLAN IDs, separated by a space or a comma. You can also specify a range of VLAN IDs for e.g. 56-78.
5.
Subinterface ID – Provide an integer between 1 and 4294967293 as the Subinterface ID. The number of subinterfaces allowed depends on your platform.
For subinterface port identification, this ID is appended to the chosen Hardware Port. For example, GigabitEthernet0.4 represents the subinterface assigned an ID of 4, operating on the port GigabitEthernet0.
Note
You cannot change the Subinterface ID after you set it.
6.
Continue configuring this interface, as described in Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
Configuring Redundant Interfaces
Beginning with Security Manager 3.2.2, you can define logical “redundant” interfaces to increase security appliance reliability. A redundant interface is a specific pair of physical interfaces, with one designated as active (or primary) and the other as standby (or secondary). If the active interface fails, the standby interface becomes active and starts passing traffic. This feature is separate from device-level failover, but you can configure redundant interfaces as well as failover, if desired. You can configure up to eight redundant interface pairs.
A redundant interface functions as a single interface (inside, outside, etc.), with only one of the member pair active at any one time. This redundant interface is configured normally, with a unique interface name, security level and IP address. Note that each member interface must be of the same type (e.g., GigabitEthernet), and cannot have a name, security level, or IP address assigned. In fact, do not configure any options other than Duplex and Speed on the member interfaces.
The redundant interface uses the MAC address of the first physical interface that you specify. If you change the order of the member interfaces in the configuration, then the MAC address changes to match the MAC address of the interface that is now listed first. Alternatively, you can explicitly assign a MAC address to the redundant interface; this address is then used regardless of the member interface MAC addresses. In either case, when the active interface fails over to the standby, the same MAC address is maintained so that traffic is not disrupted.
Note
This option is available only on PIX 8.0+ and non-5505 ASA devices.
Defining Redundant Interfaces
Follow these steps to configure two physical interfaces as a single logical “redundant interface” in the Add/Edit Interface (ASA/PIX 7.0+) dialog box, which is accessed from the device Interfaces page (see Managing Device Interfaces, Hardware Ports, and Bridge Groups).
1.
Choose Redundant as the interface Type in the Add/Edit Interface dialog box.
The Redundant ID, Primary Interface and Secondary Interface options appear.
2.
Provide an identifier for this redundant interface in the Redundant ID field; valid IDs are the integers from 1 to 8.
3.
Primary Interface – Choose the primary member of the redundant interface pair from this list of available interfaces. Available interfaces are presented by Hardware Port IDs, as named interfaces cannot be used for a redundant interface pair.
4.
Secondary Interface – Choose the secondary member of the redundant interface pair from this list of available interfaces. Available interfaces are presented by Hardware Port IDs, as named interfaces cannot be used for a redundant interface pair.
Note
Member interfaces must be enabled and of the same type (e.g., GigabitEthernet), and cannot have a Name, IP Address, or Security Level assigned. In fact, do not configure any options other than Duplex and Speed on the member interfaces.
5.
Continue configuring this interface, as described in Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
Configuring EtherChannels
Beginning with ASA 8.4.1, you can define logical EtherChannel interfaces. An EtherChannel, also called a port-channel interface, is a logical interface consisting of a bundle of individual Ethernet links (a channel group). This provides increased bandwidth and fault tolerance compared to the individual links.
An EtherChannel interface is configured and used in the same manner as a single physical interface. You can configure up to 48 EtherChannels, each of which consists of between one and eight active Fast Ethernet, Gigabit Ethernet, or Ten-Gigabit Ethernet ports. For ASA 9.2(1), the number of active interfaces increased to 16.
Note
You cannot use a redundant interface as part of an EtherChannel, nor can you use an EtherChannel as part of a redundant interface. You cannot use the same physical interfaces in a redundant interface and an EtherChannel interface. You can, however, configure both types on the ASA if they do not use the same physical interfaces.
EtherChannel MAC Addressing
All interfaces that are part of a channel group share the same MAC address. This makes the EtherChannel transparent to network applications and users, because they only see the one logical connection; they have no knowledge of the individual links. By default, the EtherChannel uses the MAC address of the lowest-numbered member interface as its MAC address.
Alternatively, you can manually configure a MAC address for the port-channel interface. We recommend doing so in case the channel interface membership changes. For example, if you remove the interface that provides the port-channel MAC address, the port-channel is assigned the MAC address of the next lowest numbered interface, causing traffic disruption. Manually assigning a unique MAC address to the EtherChannel interface prevents this disruption. (Note that in multiple-context mode, you can assign unique MAC addresses to interfaces assigned to an individual context, including EtherChannel interfaces.)
About Management Only EtherChannel Interfaces
You can specify an EtherChannel group as a management-only interface, but note the following caveats:
- Routed mode – You must explicitly configure the EtherChannel to be Management Only in the Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM). Any non-management interface added to the management-only port-channel is treated as a management port. If you add an interface already defined as management-only to the management-only group, that attribute is ignored on the physical interface. Similarly, you cannot designate an interface as management-only if it is already a member of a management-only port-channel.
- Transparent mode – In this mode, members of a management-only EtherChannel can themselves only be management-only ports. Thus, when a management-only member is added to a transparent-mode EtherChannel, the channel inherits the management-only designation, while the designation is removed from the member interface. Conversely, when such an interface is removed from the EtherChannel, the designation is restored on the individual interface.
Using an EtherChannel Interface as a Failover Link
If an EtherChannel interface is specified as a failover link, all state-sync traffic for that link will travel over a single physical interface. Should that physical interface fail, the state-sync traffic will then traverse another physical interface that is part of the EtherChannel aggregated link. If there are no remaining available physical interfaces in the EtherChannel link specified for failover, the ASA falls back to the redundant interface, if one is specified.
While an EtherChannel interface is being used as an active failover link, changes to that EtherChannel configuration are not allowed. You can change the EtherChannel configuration of that link only by disabling either the link or failover, as follows:
- Disable the EtherChannel link while the configuration changes are being made, and then reactivate it (failover will not occur while the link is disabled).
- Disable failover while the configuration changes are being made, and then re-enable it (failover will not occur in the interim).
Note
As with any other type of interface assigned as a failover link, the EtherChannel interface cannot be named. Further, none of the EtherChannel’s member interfaces can be named.
Defining EtherChannels on an ASA
Follow these steps to configure multiple physical interfaces as a single logical EtherChannel interface in the ASA Add Interface or Edit Interface dialog boxes, which are accessed from the device Interfaces page (see Managing Device Interfaces, Hardware Ports, and Bridge Groups).
Step 1
Choose EtherChannel as the interface Type.
The EtherChannel ID and interface-selection options appear on the General panel of the dialog box; the Load Balancing, LACP Mode, and Active Physical Interfaces: Minimum and Maximum fields appear on the Advanced panel.
Step 2
Provide an identifier for this EtherChannel in the EtherChannel ID field; valid IDs are the integers from 1 to 48. This number is appended to “Port-channel” to identify the EtherChannel in the Interface column of the table on the device’s Interfaces page.
Step 3
Available Interfaces – Specify the members of this port-channel group by select one or more interfaces in this list of available interfaces, and then click the >> button to add them to the member list on the right.
Note
All interfaces in the channel group must be the same type and speed. The first interface added to the channel group determines the correct type and speed.
You can assign up to 16 interfaces to a channel group. For ASA 9.2(1) and later, each channel group can have up to 16 active interfaces. For switches that support only 8 active interfaces and ASA versions earlier than 9.2(1), only eight interfaces can be active, the remaining interfaces can act as standby links in case of interface failure. Alternatively, you can create a static EtherChannel by setting LACP Mode to On (on the Advanced panel, as described below), which means all interfaces in the group can pass traffic.
Note
After assigning interfaces to this EtherChannel group, you can edit the LACP Port parameters for each member interface, as described in Editing LACP Parameters for an Interface Assigned to an EtherChannel.
Step 4
Click the Advanced tab to display that panel.
Step 5
Choose a Load Balancing option in the EtherChannel section. See About EtherChannel Load Balancing, for more information about this option.
Step 6
Select the desired LACP Mode ; the default is Active, which means up to eight interfaces are active, while up to eight are in stand-by mode, as determined by the Minimum and Maximum values under Active Physical Interfaces.
If you select On, a static port-channel is created in which all member interfaces are all “on,” meaning you can have up to 16 ports passing traffic, with no stand-by ports. When you select this option, the Mode for all interfaces assigned to this EtherChannel group is switched to On (if the Mode for each is not already On). See Editing LACP Parameters for an Interface Assigned to an EtherChannel, for more information about this mode.
Step 7
Specify the Minimum and Maximum number of Active Physical Interfaces for this EtherChannel.
As mentioned, an EtherChannel can consist of between 1 and 8 active links for ASA devices earlier than 9.2(1) or between 1 and 16 active links for ASA 9.2(1)+. Use these fields to indicate the minimum and maximum number of interfaces that can be active in this channel group at any given time. If your switch does not support 16 active interfaces, be sure to set the maximum to 8 or fewer.
Step 8
Continue configuring this interface, as described in Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
Note
The EtherChannel LACP System Priority for this device is specified in the Advanced Interface Settings (PIX/ASA/FWSM) dialog box.
Editing LACP Parameters for an Interface Assigned to an EtherChannel
After assigning interfaces to an EtherChannel (port-channel) group, you can edit the LACP Port parameters for each member interface, as described here.
Note
This feature is available only on ASA 8.4.1+ devices.
The Link Aggregation Control Protocol (LACP) directs aggregation of physical Fast Ethernet, Gigabit Ethernet, or Ten-Gigabit Ethernet interfaces into an EtherChannel group, and updating the remote partner device with current information after it finds a compatible set of ports and assigns a unique value called an “operational key” to the group. Note that operational key assignment is automatic; you cannot configure it.
Caution
These LACP parameters are not available when the EtherChannel is assigned as a failover link.
LACP System Priority
Every LACP-enabled device has a unique system ID that is formed by combining a System Priority identifier and the system’s MAC address. In certain situations, two EtherChannel-linked systems may need to change the operational key assigned to a set of ports to allow optimal aggregation. In such a situation, the system with higher priority is allowed to dynamically modify the operational key value assigned to the ports to achieve better aggregation. The system with the lower priority is not allowed to change the operational keys. The System Priority identifier is user-configurable, as described in Advanced Interface Settings (PIX/ASA/FWSM).
LACP Port Parameters
Port identification is provided by a unique number assigned to every group interface; this identifier is formed by combining a configurable Port Priority number and the port number assigned to the interface.
The port identifier provides port aggregation priority. Ports are considered for active use in an aggregation starting with the port that has highest aggregation priority in the system, and working down through an ordered list of port identifiers. The use of this port aggregation priority makes aggregation predictable and reproducible by selecting the links for aggregation in the same manner when all links are running LACP concurrently.
In addition, you can configure the priority of each port to administratively control the set of stand-by ports. For example, the port with the lowest priority will be considered last for group aggregation and will be become a stand-by port (assuming enough members are assigned to the group to allow stand-by ports).
Related Topics
Editing LACP Port Parameters for an Existing EtherChannel Interface
Follow these steps to edit an existing EtherChannel-assigned interface:
Step 1
In the table on the device’s Interfaces page, select an interface that is a Member of a Port-channel group. (See Managing Device Interfaces, Hardware Ports, and Bridge Groups for information about accessing and using this table.)
Step 2
Click Edit Row to open the Edit Interface dialog box for that interface.
Only the Enable Interface check box, the LACP Port parameters, and the Description field can be altered.
Step 3
Edit the LACP Port parameters as necessary:
- Priority – This number is combined with the port number assigned to the interface to produce a unique port identification number. This value can be 1 to 65535, with higher numbers signifying lower priorities. The default is 32768. This parameter applies only when the port is in Active or Passive mode.
- Mode – Choose one of these LACP modes:
–
Active – In Active mode, a port initiates LACP exchanges with the partner device and periodically sends updates to the partner. Active LACP reflects the port’s preference to participate in the protocol regardless of the partner’s control mode.
–
Passive – A Passive-mode port does not initiate LACP exchanges, but upon receiving a request from the partner, the port will start exchanging LACP information with the partner. Passive mode is useful when it is not clear if the remote port supports LACP.
Some devices may show undesired behavior when they do not have LACP enabled and they receive periodic LACP updates. However, for channeling to operate correctly, at least one port must be configured in Active mode.
–
On – Use this mode to configure a static port-channel in which all member interfaces are “on,” with no stand-by ports. No negotiation takes place and most restrictions associated with the other two modes do not apply; for example, the speed and duplex settings do not have to be the same for all member ports, and all member ports remain Active. Note that the remote ports also must be On. An “on” EtherChannel can only establish a connection with another “on” EtherChannel.
- VSS or vPC Switch ID – Identifies the Virtual Switching System (VSS) or Virtual Port Channel (vPC) switch ID to which the interface is connected.
Step 4
Continue editing this interface, as described in Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
About EtherChannel Load Balancing
Traffic in an EtherChannel is distributed across the individual bundled links in a deterministic fashion; however, the load is not necessarily balanced equally across all the links. Instead, frames are forwarded on a specific link as a result of a hashing algorithm. This algorithm uses a specific field or combination of fields in the packet header to produce a fixed Result Bundle Hash (RBH) value that indicates which link to use.
The algorithm can use one or a combination of the following packet-header fields to determine link assignment: source IP address, destination IP address, source MAC address, destination MAC address, TCP/UDP port numbers, or VLAN IDs. The field combination used by the algorithm is chosen from the Load Balancing list (on the Advanced tab of the ASA’s Add Interface and Edit Interface dialog boxes); these options are described in the following section. For additional information, see Configuring EtherChannels.
For example, suppose source MAC address ( src-mac) is the chosen field: when packets are forwarded to an EtherChannel, they are distributed across the ports in the channel based on the source MAC address of each incoming packet. Therefore, to provide load balancing, packets from different hosts use different ports in the channel, but packets from the same host use the same port in the channel (and the MAC addresses learned by the device do not change).
Similarly, with destination MAC address forwarding, when packets are forwarded to an EtherChannel, each packet is distributed across the ports in the channel based on the packet’s destination host MAC address. Thus, packets to the same destination are forwarded over the same port, and packets to a different destination are sent on a different port in the channel.
Therefore, when choosing a load-balancing option, use the option that provides the greatest variety in your configuration. For example, if most of the traffic on a channel is going only to a single MAC address, choosing the destination MAC address results in most of the traffic always using the same link in the channel. Alternatively, using source addresses or IP addresses might result in better load balancing, while a method that uses the source and destination addresses along with UDP or TCP port numbers can distribute traffic much differently.
Note
This option is available only on ASA 8.4.1+ devices.
Load Balancing Options
When defining a single logical EtherChannel interface in the ASA Add/Edit Interface dialog box, choose one of the following Load Balancing options (on the Add/Edit Interface Dialog Box: Advanced Tab (ASA/PIX 7.0+)) to specify the basis of load distribution:
- dst-ip – Load distribution is based on the destination-host IP address only; the source of the packets is not considered. Each packet with the same destination IP address is forwarded over the same link.
- dst-ip-port – Load distribution is based on the destination-host IP address and TCP/ UDP port. This option offers more granularity and a little more complexity than destination IP address alone.
- dst-mac – Load distribution is based on the destination host MAC address of incoming packets.
- dst-port – Distribution is based on the destination port; that is, a TCP or UDP port and not a physical interface.
- src-dst-ip – Distribution is based on source and destination IP addresses—source and destination IP addresses are paired for hash calculations. This method provides more granularity than destination IP address, for example: packets to the same destination can be forwarded over different links in a port-channel if they are coming from a different IP source.
- src-dst-ip-port – Distribution calculation considers source and destination IP addresses, and TCP/ UDP ports. Provides even greater granularity and distribution.
- src-dst-mac – Calculation is based on source and destination MAC address pairing.
- src-dst-port – Load distribution is based on source and destination TCP/UDP port.
- src-ip – Based on source host IP address only.
- src-ip-port – Source IP address and TCP/UDP port.
- src-mac – Source MAC address only.
- src-port – Source TCP/UDP port only.
- vlan-dst-ip – Destination IP address and VLAN ID pairing.
- vlan-dst-ip-port – Combination of destination IP address, TCP/UDP port, and VLAN ID.
- vlan-only – VLAN ID only.
- vlan-src-dst-ip – Source and destination IP address, and VLAN ID.
- vlan-src-dst-ip-port – Source and destination IP address, TCP/UDP port, and VLAN ID.
- vlan-src-ip – Source IP address and VLAN ID.
- vlan-src-ip-port – Source IP address, TCP/UDP port, and VLAN ID.
Configuring VNI Interfaces
VNI interfaces are similar to VLAN interfaces: they are virtual interfaces that keep network traffic separated on a given physical interface by using tagging. You apply your security policy directly to each VNI interface. All VNI interfaces are associated with the same VTEP interface.
To configure VXLAN, you must first Configuring VXLAN Policy and then create a VNI interface and associate the configured VXLAN policy to the VNI interface.
When VNI Interface is the chosen Type in the Add Interface or Edit Interface dialog box, the dialog box presents three tabbed panels of options: General, Advanced and IPv6.The following sections describe how to configure VNI interfaces using the three tabbed panels:
VNI Interfaces—General Tab
When VNI Interface is the chosen Type in the Add Interface or Edit Interface dialog box, the dialog box presents three tabbed panels of options: General, Advanced and IPv6. The options provided by the General panel are described in this section.
Navigation Path
You can access the General panel in the Add Interface and Edit Interface dialog boxes, which are accessed from the ASA Interfaces page, as described in Managing Device Interfaces, Hardware Ports, and Bridge Groups.
Related Topics
Field Reference
Table 46-2 General tab: Add/Edit Interface Dialog Box (ASA)
|
|
Enable Interface |
Check this box to enable the VNI interface if not already enabled. |
Name |
Enter the Interface Name. The name is a text string up to 48 characters, and is not case-sensitive. You can change the name by reentering this command with a new value. |
Security Level |
Enter the Security Level, between 0 (lowest) and 100 (highest). |
|
VNI ID |
Enter the VNI ID, between 1 and 10000. This ID is just an internal interface identifier. |
VNI Segment ID |
Enter the VNI Segment ID, between 1 and 16777215. The segment ID is used for VXLAN tagging. |
Multicast Group IP Address |
(Single Mode) Enter the Multicast Group IP Address. If you do not set the multicast group for the VNI interface, the default group from the VTEP source interface configuration is used, if available. If you manually set a VTEP peer IP for the VTEP source interface, you cannot specify a multicast group for the VNI interface. Multicast is not supported in multiple context mode. |
NVE Mapped to VTEP Interface |
Check the NVE Mapped to VTEP Interface check box. This setting associates the VNI interface with the VTEP source interface. |
IP Type |
Select the IP Type from the available options. |
Static IP |
IP Address—(Routed Mode) In the IP Address area, configure an IPv4 address. To configure IPv6, click the IPv6 tab. Subnet Mask—Specify the Subnet Mask. |
Use DHCP |
DHCP Learned Route Metric—(Required)To assign an administrative distance to the learned route, enter a value between 1 and 255 in the DHCP Learned Route Metric field. If this field is left blank, the administrative distance for the learned routes is 1. Obtain Default Route using DHCP—(Optional) Select this option to obtain a default route from the DHCP server so that you do not need to configure a default static route. Enable Tracking for DHCP Learned Route—(Optional) If Obtain Default Route using DHCP is selected, you can select this option to enable route tracking via a specific Service Level Agreement (SLA) monitor. The following option becomes available: Tracked SLA Monitor—Required if Enable Tracking for DHCP Learned Route is selected. Enter or Select the name of the SLA monitor object that defines the route tracking (connectivity monitoring) to be applied to this interface. |
Description |
(Optional) Specify a description for the interface. |
VNI Interfaces—Advanced Tab
When VNI Interface is the chosen Type in the Add Interface or Edit Interface dialog box, the dialog box presents three tabbed panels of options: General, Advanced and IPv6. The options provided by the Advanced panel are described in this section.
Navigation Path
You can access the Advanced tab in the Add Interface and Edit Interface dialog boxes, which are accessed from the ASA Interfaces page, as described in Managing Device Interfaces, Hardware Ports, and Bridge Groups.
Related Topics
Field Reference
Table 46-3 Advanced tab: Add/Edit Interface Dialog Box (ASA)
|
|
Active MAC Address |
Use the Active MAC Address field to manually assign a private MAC address to the interface |
Standby MAC Address |
The Standby MAC Address field can be used to set a standby MAC address for use with device-level failover. |
Roles |
All interface roles assigned to this interface are listed in this field. Role assignments are based on pattern matching between the Name given to this interface and all currently defined Interface Role objects in Cisco Security Manager. Interface role objects are replaced with the actual interface IP addresses when the configuration is generated for each device. They allow you to define generic rules—ones that can apply to multiple interfaces. |
DHCP Relay Servers |
Enter the IP address or select a Networks/Hosts object representing the interface-specific DHCP server to which DHCP requests on this interface are relayed. Use a comma to separate multiple values. You can configure a maximum of 4 interface-specific DHCP relay servers and a maximum of 10 global and interface-specific DHCP relay servers combined. |
DHCP Relay Trust Info (Option 82) |
Specifies that you want to trust this DHCP client interface. You can configure interfaces as trusted interfaces to preserve DHCP Option 82. |
VNI Interfaces—IPv6 Tab
When VNI Interface is the chosen Type in the Add Interface or Edit Interface dialog box, the dialog box presents three tabbed panels of options: General, Advanced and IPv6. The options provided by the IPv6 panel are described in this section.
Navigation Path
You can access the IPv6 panel in the Add Interface and Edit Interface dialog boxes, which are accessed from the ASA Interfaces page, as described in Managing Device Interfaces, Hardware Ports, and Bridge Groups.
Related Topics
Field Reference
Table 46-4 IPv6 tab: Add/Edit Interface Dialog Box (ASA)
|
|
Enable IPv6 |
Check this box to enable IPv6 and configure IPv6 addresses on this interface. You can deselect this option to disable IPv6 on the interface, but retain the configuration information. |
Enforce EUI-64 |
When selected, use of Modified EUI-64 format interface identifiers in IPv6 addresses on a local link is enforced. When this option is enabled on an interface, the source addresses of IPv6 packets received on the interface are verified against the source MAC addresses to ensure that the interface identifiers use the Modified EUI-64 format. If the interface identifier in an IPv6 packet is not in the Modified EUI-64 format, the packet is dropped and the following system log message is generated: %PIX|ASA-3-325003: EUI-64 source address check failed. Address format verification is performed only when a flow is created. Packets from an existing flow are not checked. Additionally, address verification can be performed only for hosts on the local link. Packets received from hosts behind a router will fail the address format verification, and be dropped, because their source MAC address will be the router MAC address and not the host MAC address. The Modified EUI-64 format interface identifier is derived from the 48-bit link-layer (MAC) address by inserting the hex number FFFE between the upper three bytes (OUI field) and the lower 3 bytes (serial number) of the link-layer address. To ensure the chosen address is from a unique Ethernet MAC address, the next-to-lowest order bit in the high-order byte is inverted (universal/local bit) to indicate the uniqueness of the 48-bit address. For example, an interface with a MAC address of 00E0.B601.3B7A would have a 64-bit interface ID of 02E0:B6FF:FE01:3B7A. |
DAD Attempts |
To specify the number of consecutive neighbor solicitation messages that are sent on an interface during duplicate address detection (DAD), enter a number from 0 to 600 in this field. Entering 0 disables duplicate address detection on the interface. Entering 1 configures a single transmission without follow-up transmissions; this is the default. Duplicate address detection verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection uses neighbor solicitation messages to verify the uniqueness of unicast IPv6 addresses. When duplicate address detection identifies a duplicate address, the state of the address is set to DUPLICATE and the address is not used. If the duplicate address is the link-local address of the interface, the processing of IPv6 packets is disabled on the interface and an error message similar to the following is issued: %PIX-4-DUPLICATE: Duplicate address FE80::1 on outside If the duplicate address is a global address of the interface, the address is not used and an error message is issued, similar to that shown previously for a duplicate link-local address. All configuration commands associated with the duplicate address remain as-configured while the state of the address is set to DUPLICATE. If the link-local address for an interface changes, duplicate address detection is performed on the new link-local address, and all other IPv6 address associated with the interface are regenerated (that is, duplicate address detection is performed only on the new link-local address). |
NS Interval |
The interval between IPv6 neighbor solicitation retransmissions, in milliseconds. Valid values range from 1000 to 3600000 milliseconds; the default value is 1000 milliseconds. Note This value is included in all IPv6 router advertisements sent out on this interface. |
Reachable Time |
The amount of time, in milliseconds, within which a remote IPv6 node is considered still reachable, after initial reachability was confirmed. Valid values range from 0 to 3600000 milliseconds, the default value is 0. When 0 is used for the value, the reachable time is set as undetermined—it is up to the receiving devices to set and track reachable time. A configured time enables detection of unavailable neighbors. A shorter time allows detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation. |
Managed Config Flag |
Whether or not to set the flag "managed-config-flag" in the IPv6 router advertisement packet. |
Other Config Flag |
Whether or not to set the flag "other-config-flag" in the IPv6 router advertisement packet. |
Enable RA |
When checked, IPv6 router advertisement transmissions are enabled on the interface. The following options are enabled:
- RA Lifetime – The “router lifetime” value specifies how long nodes on the local link should consider the security appliance as the default router on the link. Valid values range from 0 to 9000 seconds; the default is 1800 seconds. Entering 0 indicates that the security appliance should not be considered a default router on the selected interface.
Any non-zero value should not be less than the following RA Interval value. Note This value is included in all IPv6 router advertisements sent out on this interface.
- RA Interval – The interval between IPv6 router advertisement transmissions on this interface. Valid values range from 3 to 1800 seconds, (or from 500 to 1800000 milliseconds if the following RA Interval in Milliseconds option is checked); the default is 200 seconds.
The interval between transmissions should be less than or equal to the RA Lifetime value if it is non-zero. To prevent synchronization with other IPv6 nodes, randomly adjust the actual value used to within 20 percent of the desired value.
- RA Interval in Milliseconds – Checking this option indicates that the provided RA Interval value is in milliseconds, rather than seconds.
|
Interface IPv6 Addresses |
The IPv6 addresses assigned to the interface are specified in this section of the dialog box.
- Link-Local Address – To override the link-local address that is automatically generated for the interface, enter the desired IPv6 link-local address in this field.
The link-local address is composed of the link-local prefix FE80::/64 and the interface ID in Modified EUI-64 format. For example, an interface with a MAC address of 00E0.B601.3B7A would have a link-local address of FE80::2E0:B6FF:FE01:3B7A. An error will occur if another host is using the specified address.
- Enable Address Auto-Configuration – Select this option to enable automatic configuration of IPv6 addresses on the interface using stateless autoconfiguration. The addresses are configured based on the prefixes received in Router Advertisement (RA) messages. If a link-local address has not been configured, then one is automatically generated for this interface. An error occurs if another host is already using the generated link-local address.
– Trust the DHCP Servers for default gateway – Select this radio button to install a default route from Router Advertisements that come from a trusted source - the directly-connected network. – Ignore trust and accept router advertisements – Select this radio button to install a default route from Router Advertisements that come from another network.
- The table in this section displays the IPv6 addresses assigned to this interface. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.)
Add Row and Edit Row open the IPv6 Address for Interface Dialog Box. |
Interface IPv6 Prefixes |
Use the table in this section to configure which IPv6 prefixes (that is, the network portion of the IPv6 addresses) are included in IPv6 router advertisements. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.) Add Row and Edit Row open the IPv6 Prefix Editor Dialog Box. |
Interface IPv6 DHCP |
|
Configuring Tunnel Interface
Cisco Security Manager 4.13 supports route based VPN method for the Site-to-Site VPN. This support requires configuration of the static crypto map access list and mapping it to an interface. Due to this requirement, Large Enterprises and Virtual Private Clouds need to track all remote subnets and include them in the crypto map access list. To overcome this challenge, ASA 9.7.1 is enhanced to support the route based VPN method using the VTI (Virtual Tunnel Interface). Thus, beginning with Cisco Security Manager 4.13, you can define tunnel interface for the VPN and its associated IPSec policy.
VTI is supported only for Regular IPsec with Hub and Spoke, and Point to Point VPN topologies. VTI is not supported for other topologies like Full Mesh Topology, Extranet VPN Topology and RAVPN Policies.
In a multi- hub and multi- spoke scenario, for the tunnel interface to establish connectivity from one peer to another peer, ensure interface roles are applied to the hubs and spokes.
Note
The Advanced tab and IPv6 tab options are not applicable for VTI.
The following sections describe how to configure tunnel interface:
Tunnel—General Tab
In the Add Interface or Edit Interface dialog box, when you select Tunnel from the Type drop-down, the dialog box displays three tabs: General, Advanced, and IPv6. This section describes the options provided by the General panel.
Navigation Path
You can access the General panel from the ASA Interfaces page, as described in Managing Device Interfaces, Hardware Ports, and Bridge Groups.
Related Topics
Field Reference
Table 46-5 General tab: Add/Edit Interface Dialog Box (ASA)
|
|
Enable Interface |
Check this box to enable the tunnel interface if not already enabled. |
Name |
Enter the Interface Name. The name is a text string up to 48 characters, and is not case-sensitive. You can change the name by reentering this command with a new value. |
|
Tunnel ID |
Enter the unique Tunnel ID, between 0 and 100. This ID is an internal interface identifier. The specified ID is mapped with the interface name. The Name and the ID pair must be unique. This field is mandatory for Regular IPSEC VTI VPN. |
Source Interface |
Enter the source interface to be used for creating the VTI, IP address shall be picked up from this interface. Click the Select button to choose the source interface from the available interfaces. For more information, see Selecting Objects for Policies. Note Tunnel source and destination pair must be unique. |
Destination IP/Hostname |
The tunnel destination IP address to be used for the VTI. Beginning with 4.14, Cisco Security Manager allows you to specify a Hostname as the destination IP. Note Tunnel source and destination pair has to be unique. |
IPv4 Mode |
Check the check box to pass IPv4 as the tunnel protection mode, currently, only IPSec is supported. IPv4 network would be encapsulated in the tunnel. |
IPSec Profile |
Enter the IPSec profile to be attached to the tunnel interface. A policy object must have been created in the Policy Object Manager. For information on creating Policy Object, refer Configuring IPSec Policy for Tunnel Interface. Note If you select IPSec profiles with different IKEV1 transform sets for the peers, Cisco Security Manager will create the tunnel interface, but the connectivity between the two peers will not be established. To choose the profile from the IPSec Object Selector dialog, click the Select button. For more information, see Selecting Objects for Policies. Note When you specify the policy, ensure tunnel name is entered. Cisco Security Manager displays error message when the Name field is blank. |
IP Type |
From the drop-down, select Static IP.
- IP Address—(Routed Mode) In the IP Address area, configure an IPv4 address. To configure IPv6, click the IPv6 tab.
- Subnet Mask—Specify the Subnet Mask.
|
Description |
(Optional) Specify a description for the interface. |
Establishing Regular IPSec VPN Tunnel
The following checkpoints (while configuring the Tunnel - Configuring Tunnel Interface) help you to successfully establish the Regular IPSec VPN Tunnel connectivity:
1.
You must enter Tunnel ID value.
2.
Source interface must be configured and must be reachable to its peer through ISP or routing.
3.
You must enter the peer source interface IP address in the Destination IP field.
4.
For the IPSec Profile field:
a.
Select the same IKEV1 transform set for both the peer devices.
b.
In Point-to-Point topology, either one of the peers must be the responder.
c.
In Hub and Spoke topology, select the Hub as the responder; select all spokes as initiators.
5.
IPV4 mode must be configured for enabling the interesting traffic.
6.
You must enter IP address to establish the VPN, dynamic IP address is not supported.
7.
Select Static or BGP routing for enabling the interesting traffic. In case of firewall policy, VTI is supported only in static routing.
Note
Cisco Security Manager displays error message if BGP/Static route is not configured properly for Point-to-Point topology, and Hub and Spoke topology with one hub and one spoke. For Multi hub/spoke scenario, the error message is not displayed.
Configuring IPSec Policy for Tunnel Interface
Use the IPsec Policy page to configure the IPsec policy used during IKE Phase 1 and IKE Phase 2 negotiations for Regular IPsec with Hub and Spoke and Point to Point VPN topologies.
Navigation Path
- Choose Manage > Policy Objects to open the Policy Object Manager. Under All Object Types, click IPSec Profile. To add a profile, click the Add button.
Field Reference
Table 46-6 IPsec Profile
|
|
Name |
Name of the IPSec policy. |
Description |
Description for the policy. |
IKE Version |
Choose the relevant IKE version— IKEv1 or IKEv2. Note Beginning with 4.14, Cisco Security Manager supports IKEv2. However, at a time, you can choose only one version of IKE. |
IKEv1 Transform Sets |
The IKEv1 transform sets to be used for your tunnel policy. Transform sets specify which authentication and encryption algorithms are used to secure the traffic in the tunnel. You can select up to 11 transform sets. For more information, see Understanding Transform Sets. Transform sets may use only tunnel mode IPsec operation. You can associate more than one IKEv1 Transform Sets. If more than one of your selected transform sets is supported by both peers, the transform set that provides the highest security is used. Note For the tunnel to be functional, IKEv1 transform set on both peers should be the same. Click Select to select the IPSec transform set policy objects to use in the topology. If the required object is not yet defined, you can click the Create (+) button beneath the available objects list in the selection dialog box to create a new one. For more information, see Configuring IPSec IKEv1 or IKEv2 Transform Set Policy Objects. This field is not available for IKEv2. |
IKEv2 IPSec Proposal (ASA 9.8(1) Onwards) |
Click Select to select the IPSec proposals to be used for your tunnel policy. Cisco Security Manager allows you to select more than one proposals. <check on the VM> If the required object is not yet defined, you can click the Create (+) button beneath the available objects list in the selection dialog box to create a new one. For more information, see Configuring IPSec IKEv1 or IKEv2 Transform Set Policy Objects. This field is not available for IKEv1. |
Trustpoint (ASA 9.8(1) Onwards) |
Click Select to select the CA servers for issuing certificates to the participating IPSec network devices. The peers that are configured with this policy obtains digital certificates from the selected CA server. You can specify only one trustpoint. For IKEv1, when trustpoint is used for authentication, the initiator should have the trustpoint specified under IPSec profile’s trustpoint configuration; and for responder, the trustpoint should be specified under tunnel-group CLI (similar to non-VTI configuration). For IKEv2, when trustpoint is used for authentication, the trustpoint CLI is specified under tunnel-group CLI for both initiator and responder. |
Certificate Chain (ASA 9.8(1) Onwards) |
Select the check box to enable sending of the certificate chain for authorization. A certificate chain includes the root CA certificate, identity certificate, and key pair. |
Responder Only |
Check this check box to set the peer that is associated with this policy acts as the responder. Ensure only one of the peer is configured with the responder only settings. |
Enable Perfect Forward Secrecy (PFS) Modulus Group |
Whether to enable the use of Perfect Forward Secrecy (PFS) to generate and use a unique session key for each encrypted exchange. In IPsec negotiations, PFS ensures that each new cryptographic key is unrelated to any previous key. If you select this option, also select the Diffie-Hellman key derivation algorithm to use when generating the PFS session key in the Modulus Group list. For an explanation of the options, see Deciding Which Diffie-Hellman Modulus Group to Use. The following Modulus Group is not supported for IKEv1. Ensure you do not select them for IKEv1:
- group14
- group19
- group20
- group21
- group24
|
Lifetime (Seconds) Lifetime (Kilobytes) |
The global lifetime settings for the Crypto IPsec security association (SA). You can specify the IPSec lifetime in seconds, in kilobytes, or both.
- Seconds—The number of seconds an SA will exist before expiring. Enter a value within the range 120-2147483647 seconds.
- Kilobytes—The volume of traffic (in kilobytes) that can pass between IPsec peers using a given SA before it expires. Valid values depend on the device type. Enter a value within the range 10-2147483647.
To allow unlimited You can select Enable Unlimited Lifetime (Kilobytes) check box. |
Category |
The category assigned to the object. Categories help you organize and identify rules and objects. See Using Category Objects. |
Allow Value Override per Device |
Select to allow the properties of this object to be redefined on individual devices. If you allow device overrides, you can click the Edit button to create, edit, and view the overrides. The Overrides field indicates the number of devices that have overrides for this object. |
Managing Device Interfaces, Hardware Ports, and Bridge Groups
The Interfaces page displays the interfaces, subinterfaces, redundant interfaces, virtual interfaces (VLANs), and EtherChannel interfaces, as well as the hardware ports and bridge groups, configured on the selected device, and lets you add, edit and delete them.
The types of interface available depend on device type, operating system version, and mode (routed or transparent). For example, EtherChannel interfaces are available only on ASA 8.4.1 and later devices, in both routed and transparent mode. See Understanding Device Interfaces for more information.
Note
The Interfaces page displayed for ASA 5505 devices presents two tabbed panels: Interfaces and Hardware Ports. Similarly, the Interfaces page displayed for both Firewall Services Modules (FWSMs), version 3.1 and later, and ASAs version 8.4.1 and later, operating in transparent mode also present two tabbed panels: Interfaces and Bridge Groups. Links to configuration information for these features are included in the following procedure.
Each security device must be configured, and each active interface must be enabled. Inactive interfaces can be disabled. When disabled, the interface does not transmit or receive data, but its configuration information is retained.
If you bootstrapped a new security device, the set-up feature configures only the addresses and names associated with the inside interface. You must define the remaining interfaces on that device before you can specify access and translation rules for traffic traversing that security device.
Transparent firewall mode allows only two interfaces to pass traffic; however, if your platform includes a dedicated management interface, you can use it (either the physical interface or a subinterface) as a third interface for management traffic.
Follow these general steps to manage security-device interfaces and related options. You can add, edit and delete configured interfaces, subinterfaces, redundant interfaces, virtual interfaces (VLANs), EtherChannel interfaces, hardware ports, and bridge groups, according to the type of device selected.
Step 1
Ensure Device View is your present application view; if necessary, click the Device View button on the toolbar.
Note
For more information on using the Device View to configure device policies, see Managing Policies in Device View and the Site-to-Site VPN Manager).
Step 2
Select the security device you want to configure.
Step 3
Select Interfaces in the Device Policy selector.
The Interfaces page is displayed. The information displayed, and the page itself, varies based on the selected device type and version, the operational mode (routed versus transparent), and whether the device hosts single or multiple contexts.
Note that the Interfaces page for ASA 5505 devices presents two tabbed panels: Hardware Ports and Interfaces. Similarly, the Interfaces page displayed for both FWSMs (version 3.1 and later) and ASAs (version 8.4.1 and later), operating in transparent mode also presents two tabbed panels: Interfaces and Bridge Groups.
Step 4
Add, edit and delete interfaces and related options, as necessary.
The Interfaces pages/panels and the Bridge Groups and Hardware Ports panels present standard Security Manager tables, with Add Row, Edit Row and Delete Row buttons, which are described in Using Tables.
The actual dialog box presented when you click the Add Row or Edit Row button depends on the type of device (and panel) you have selected. Refer to the following topics for device-specific dialog box information:
Step 5
To manage Advanced Interface settings, including enabling communication between interfaces with the same security level, click the Advanced button at the bottom of the Interfaces page to open the Advanced Interface Settings dialog box. See Advanced Interface Settings (PIX/ASA/FWSM) for more information.
Step 6
When you are finished adding, editing and deleting interfaces, click Save at the bottom of the window to save your interface definitions to the Cisco Security Manager server.
Add/Edit Interface Dialog Box (PIX 6.3)
Table 46-7 Add/Edit Interface Dialog Box (PIX 6.3)
|
|
Enable Interface |
Enables this interface to pass traffic. In addition to this setting, you must specify an IP Type and a Name before traffic can pass according to your security policy. You must enable a physical interface before traffic can pass through any enabled subinterfaces. |
Type |
Choose the type of interface:
- Physical – VLAN is on the same network as its underlying hardware interface.
- Logical – VLAN is associated with a logical interface.
|
Name |
Provide an interface name up to 48 characters in length. The Name should be a memorable name for the interface that relates to its use. Supported interface names are:
- Inside—Connects to your internal network. Must be most secure interface.
- DMZ—Demilitarized zone (Intermediate interface). Also known as a perimeter network.
- Outside—Connects to an external network or the Internet. Must be least secure interface.
|
Hardware Port |
When defining a physical network interface, this value represents the name identifies the interface type and its slot or port in the device. When you add a logical network interface, you can choose any enabled physical interface to which you want to add a logical interface. If you do not see the desired hardware port, verify that the interface is enabled. Valid values are:
- ethernet0 to ethernet n.
- gb-ethernet n.
where n represents the number of network interfaces in the device. |
IP Type |
The IP Type defines the type of IP addressing used for the interface; choose Static IP or Use DHCP, as described in Device Interface: IP Type (PIX 6.3). (The PPPoE option is not applicable to PIX 6.3 devices.) Note You can configure DHCP only on the outside interface of a security appliance. |
Speed and Duplex |
Lists the speed options for a physical interface; not applicable to logical interfaces. Choose one of the following options:
- auto – Sets Ethernet speed automatically. The auto keyword can be used only with the Intel 10/100 automatic speed-sensing network interface card.
- 10baset – 10-Mbps Ethernet half-duplex.
- 10full – 10-Mbps Ethernet full-duplex.
- 100basetx – 100-Mbps Ethernet half-duplex.
- 100full – 100-Mbps Ethernet full-duplex.
- 1000auto – 1000-Mbps Ethernet to auto-negotiate full- or half -duplex.
Tip We recommend that you do not use this option to maintain compatibility with switches and other devices in your network.
- 1000full – Auto-negotiate, advertising 1000-Mbps Ethernet full-duplex.
- 1000full nonnegotiate – 1000-Mbps Ethernet full-duplex.
- aui – 10-Mbps Ethernet half-duplex communication with an AUI cable interface.
- bnc – 10-Mbps Ethernet half-duplex communication with a BNC cable interface.
Note We recommend that you specify the speed of the network interfaces in case your network environment includes switches or other devices that do not handle autosensing correctly. |
MTU |
Specify the maximum packet size in bytes; that is, the maximum transmission unit (MTU). The value depends on the type of network connected to the interface. Valid values are 300 to 65535 bytes. Default is 1500. |
Physical VLAN ID |
For a physical interface, enter the VLAN ID, between 1 and 4094. This VLAN ID must not be in use on connected devices. |
Logical VLAN ID |
Provide the alias, a value between 1 and 4094, for the VLAN associated with this logical interface. This value is required if the logical interface Type is selected. |
Security Level |
Specify the security level of the interface: enter a value between 0 (least secure) and 100 (most secure). The security appliance lets traffic flow freely from an inside network to an outside network (lower security level). Many other security features are affected by the relative security level of two interfaces.
- The outside interface is always 0.
- The inside interface is always 100.
- DMZ interfaces are between 1 and 99.
|
Roles |
For more information on roles and how to define and use them, see Understanding Interface Role Objects. All interface roles assigned to this interface are listed in this field. Role assignments are based on pattern matching between the Name given to this interface and all currently defined Interface Role objects in Cisco Security Manager. Interface role objects are replaced with the actual interface IP addresses when the configuration is generated for each device. They allow you to define generic rules—ones that can apply to multiple interfaces. For more information on roles and how to define and use them, see Understanding Interface Role Objects. |
Device Interface: IP Type (PIX 6.3)
A PIX 6.3 security device requires IP addressing for its interfaces; however, firewall interfaces do not have IP addresses until you assign them.
The Add/Edit Interface dialog box presented for a PIX 6.3 security device includes the section IP Type, where you specify the type of IP addressing for the interface and provide related parameters, as described here. See Add/Edit Interface Dialog Box (PIX 6.3) for information about the other sections of the dialog box.
Note
The IP Type options presented for other security appliances are described in Device Interface: IP Type (PIX/ASA 7.0+).
Step 1
In the Add/Edit Interface dialog box, choose a method for address assignment from the IP Type list, and then provide related parameters, as follows:
- Static IP – Provide a static IP Address and Subnet Mask that represents the security device on this interface’s connected network. The IP address must be unique for each interface.
The Subnet mask can be expressed in dotted decimal format (for example, 255.255.255.0), or by entering the number of bits in the network mask (for example, 24). Beginning from Version 4.13, Cisco Security Manager allows 255.255.255.254 for a point to point interface. Do not use 255.255.255.255 for an interface connected to the network because this will stop traffic on that interface. If you omit the Subnet Mask value, a “classful” network is assumed, as follows:
–
The Class A netmask (255.0.0.0) is assumed if the first octet of the IP Address is 1 through 126 (i.e., addresses 1.0.0.0 through 126.255.255.255).
–
The Class B netmask (255.255.0.0) is assumed if the first octet of the IP Address is 128 through 191 (i.e., addresses 128.0.0.0 through 191.255.255.255).
–
The Class C netmask (255.255.255.0) is assumed if the first octet of the IP Address is 192 through 223 (i.e., addresses 192.0.0.0 through 223.255.255.255).
Note Do not use addresses previously used for routers, hosts, or any other firewall device commands, such as an IP address in the global pool or a static NAT entry.
- Use DHCP – Enables Dynamic Host Configuration Protocol (DHCP) for automatic assignment of an IP address from a DHCP server on the connected network. The following options become available:
–
Obtain Default Route using DHCP – Check this box to obtain a default route from the DHCP server so that you do not need to configure a default static route.
–
Retry Count – The number of times the PIX will resend the DHCP request. Valid values are 4 to 16; the default is 2
- PPPoE (PIX and ASA 7.2+) – This option does not apply to PIX 6.3 devices.
Note
You can configure DHCP only on the outside interface of a firewall device.
Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM)
These Add Interface and Edit Interface dialog boxes are used to define and configure interfaces, subinterfaces, redundant, and EtherChannel interfaces on PIX 7.0+, ASA, and FWSM devices. You can access the Add/Edit Interface dialog boxes from the Interfaces page. See Managing Device Interfaces, Hardware Ports, and Bridge Groups for more information.
Note
The ASA 5505, combining switch and security appliance features, is a special case in that you configure both physical switch ports and logical VLAN interfaces. Thus, the Interfaces page displayed for ASA 5505 devices presents two tabbed panels: Hardware Ports and Interfaces. See Understanding ASA 5505 Ports and Interfaces for more information.
ASA 8.4.1+ and FWSM 3.1+ devices operating in transparent mode also present two tabbed panels: Interfaces and Bridge Groups. See Add/Edit Bridge Group Dialog Box for information about configuring bridge groups.
Many of the parameters presented in these dialog boxes vary according to device type and version, operational mode (routed versus transparent), and whether the device hosts a single or multiple contexts.
Note
If you intend to use an interface for failover, you can define that interface in the Add Interface dialog box but do not configure it; instead, use the Failover page (see Chapter 50, “Configuring Failover”). In particular, do not specify an interface Name, as this parameter disqualifies the interface from being used as the failover link.
Using the Add Interface and Edit Interface Dialog Boxes
The following steps outline the general use of these dialog boxes:
1.
An interface Type drop-down list appears at the top of the Add Interface and Edit Interface dialog boxes.
Note
Catalyst 6500 services modules (ASA-SMs and FWSMs) and the ASA 5505 do not present the Type list.
Depending on device type, operating-system version and operating mode (router or transparent), the Type options presented will be two, three or all of the following:
–
Physical Interface – Choose this option to configure a physical interface on the device.
–
Sub-Interface – Choose this option to configure a logical interface (or VLAN connection) associated with a previously defined physical interface. Refer to Configuring Subinterfaces (PIX/ASA) for more information.
–
Redundant – Choose this option to configure two physical interfaces as a single logical “redundant interface.” Refer to Configuring Redundant Interfaces for more information.
–
EtherChannel – Choose this option to configure a logical interface consisting of a bundle of up to eight individual Ethernet links; this bundle is known as an EtherChannel, or a port-channel interface. (This option is available only on ASA 8.4+ devices.) Refer to Configuring EtherChannels, for more information.
–
VNI Interface – Choose this option to configure a VNI interface. They are virtual interfaces that keep network traffic separated on a given physical interface by using tagging. You apply your security policy directly to each VNI interface. All VNI interfaces are associated with the same VTEP interface. Refer to Configuring VNI Interfaces, for more information.
–
Tunnel– Choose this option to configure a logical interface -VTI, to support route based VPN method for the Site-to-Site VPN topologies. Refer to Configuring Tunnel Interface, for more information.
2.
Below the Type option, the dialog boxes present up to three tabbed panels. Again, this depends on device type, operating-system version and operating mode.
The PIX 7.0+ Add Interface and Edit Interface dialog boxes present two tabbed panels: General and Advanced. The ASA 7.0+ Add Interface and Edit Interface dialog boxes present three tabbed panels: General, Advanced and IPv6.
–
Configure the General options, as appropriate. This panel is described in Add/Edit Interface Dialog Box: General Tab (PIX 7.0+/ASA/FWSM).
–
Configure the Advanced-panel options, as appropriate. This panel is described in Add/Edit Interface Dialog Box: Advanced Tab (ASA/PIX 7.0+).
–
Configure the IPv6 options, as appropriate. This panel is described in Configuring IPv6 Interfaces (ASA/FWSM).
3.
When you have finished configuring this interface, click OK to close the dialog box and return to the device Interfaces page.
Add/Edit Interface Dialog Box: General Tab (PIX 7.0+/ASA/FWSM)
The Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM), is used to define and configure interfaces, subinterfaces, VLAN interfaces, and redundant, and EtherChannel interfaces on firewall devices. You can access the Add/Edit Interface dialog box from the Interfaces page. See Managing Device Interfaces, Hardware Ports, and Bridge Groups for more information.
Note
In the following descriptions, the term “interface” may be used generically to refer to any of these types of interface.
The General panel of this dialog box is used to configure general interface settings, including Name, Security Level and IP Type parameters. Note that many of the parameters presented in this panel vary according to device type and version, operational mode (routed versus transparent), and whether the device hosts a single or multiple contexts. Thus, some of the options in the following table may not appear for the device you are configuring.
Related Topics
Table 46-8 General tab: Add/Edit Interface Dialog Box
|
|
Enable Interface |
Enables this interface to pass traffic. By default, all physical interfaces are shut down. Traffic cannot traverse an interface of any type if the interface is not enabled. If you are defining a logical interface such as a subinterface, enable the physical interface it will be associated with before defining the subinterface. If you are defining a redundant interface or an EtherChannel interface, enable the member interfaces before defining the group interface. When you check this option, you must also specify a Name and, in routed mode, an IP Type (or IP Address and Subnet Mask on an FWSM or ASA-SM) before traffic can pass according to your security policy. In multiple-context mode, if you allocate a physical or logical interface to a context, the interface is enabled by default in the context. However, before traffic can pass through the context interface, you must also enable the interface in the system configuration. If you shut down an interface in the system execution space, that interface is shut down in all contexts in which it shared. |
Management Only |
Reserves this interface for device administration. Only traffic for management of this device is accepted; pass-through traffic for other interfaces and devices is rejected. You cannot set a Primary or Secondary ISP interface to be Management Only. Defining a management-only EtherChannel interface has certain member-interface restrictions. See Configuring EtherChannels, for more information. Note This is not available on devices in transparent mode. If an interface is assigned as Management Only, then Route Map cannot be assigned to that interface. In other words, either Management Only or Route Map can be assigned to an interface but not both. |
Interface |
On the ASA 5505, the Hardware Port is specified on the Hardware Ports panel (see Configuring Hardware Ports on an ASA 5505). Also, this option is not part of Catalyst 6500 services module (ASA-SM and FWSM) configuration. For a physical interface, provide the specific hardware port assigned to the interface: enter a physical port ID, which includes network type, slot and port number, in the form: type[slot/]port. This is also the name by which subinterfaces can be associated with the interface. The network type specified for the physical interface can be either Ethernet or GigabitEthernet; on the ASA 5580, TenGigabitEthernet is also available. This field provides automatic pattern matching: if you begin typing with the letter e, “Ethernet” is inserted into the field. Similarly, typing the letter g produces “GigabitEthernet.” Therefore, valid values are:
- Ethernet0 to Ethernet n
- GigabitEthernet0 to GigabitEthernet n
- GigabitEthernet s / n
- TenGigabitEthernet s / n (ASA 5580 only)
where s represents a slot number, and n represents a port number, up to the maximum number of network ports in the slot or device. For an ASA 5500 series appliance, enter the type and a slot/port pair; for example, gigabitethernet0/1. Ports that are built into the chassis are assigned to slot 0, while ports on the 4-Port Gigabit Ethernet Security Services Module (4GE SSM) are assigned to slot 1. When you enter a slot/port pair, the Media Type options are enabled. The ASA 5500 series appliances also include a management interface type. The management interface is a Fast Ethernet interface designed for device-management traffic only, and is specified as management0/0. You can, however, use this physical interface for through traffic if desired (be sure the Management Only option is not selected). Thus, in transparent firewall mode, you can use the management interface in addition to the two interfaces allowed for through traffic. You can also add subinterfaces to the management interface to provide management in each security context in multiple-context mode. If you are defining a subinterface, you can simply choose the desired Hardware Port from a list of previously defined ports (you must also supply a VLAN ID). If you do not see a desired interface ID, be sure that Interface is defined and enabled. |
Name |
Provide an identifier for this interface of up to 48 characters in length. The name should be a memorable name for the interface that relates to its use. However, if you are using failover, do not name interfaces that you are reserving for failover communications; this includes an EtherChannel intended for failover, as well as its member interfaces. Also, do not name interfaces intended for use as a member of a redundant-interface pair. Certain names are reserved for specific interfaces, in accordance with the interface naming conventions of the security appliance. As such, these reserved names enforce default, reserved security levels, as follows:
- Inside – Connects to your internal network. Must be the most secure interface.
- DMZ – “Demilitarized zone” attached to an intermediate interface. DMZ is also known as a perimeter network. You can name a DMZ interface any name you choose. Typically, DMZ interfaces are prefixed with “ DMZ ” to identify the interface type.
- Outside – Connects to an external network or the Internet. Must be the least secure interface.
Similarly, a subinterface name typically identifies its associated interface, in addition to its own unique identifier. For example, DMZoobmgmt could represent an out-of-band management network attached to the DMZ interface. Note Again, do not name the interface if you intend to use it for failover, or as a member of a redundant interface. See Chapter 50, “Configuring Failover” and Configuring Redundant Interfaces for more information. |
Security Level |
Specify the security level of the interface: enter a value between 0 (least secure) and 100 (most secure). The security appliance lets traffic flow freely from an inside network to an outside network (lower security level). Many other security features are affected by the relative security level of two interfaces.
- The outside interface is always 0.
- The inside interface is always 100.
- DMZ interfaces are between 1 and 99.
|
Media Type |
When Interface is the chosen Type and you enter a hardware port ID with slot/port numbers in the Hardware Port field, these options are enabled. (These options apply to ASA slot/port interfaces only.) For all ASA 5500 series appliances, except the 5505, ports that are built into the chassis are assigned to slot 0, while ports on the 4GE SSM are assigned to slot 1. By default, all connectors used on an ASA are RJ-45 connectors. However, the ports on the 4GE SSM can include fiber SFP connectors. As part of the interface configuration for one of these fiber-based connections, you must change the Media Type setting from the default (RJ45) to the fiber-connector setting (SFP). Fiber-based interfaces do not support duplexing and have a fixed speed, so the Duplex option is disabled, and the Speed options are limited to auto and nonegotiate. Select the connector type used by this slot-1 interface:
- RJ45 – The port uses RJ-45 (copper) connectors.
- SFP – The port uses fiber SFP connectors. Required for 10-Gigabit Ethernet cards.
|
VLAN ID |
When Subinterface is the chosen interface Type, or when you are defining a logical interface on a device operating in transparent mode, on an ASA 5505, or on a Catalyst 6500 services module (ASA-SM or FWSM), provide a VLAN ID for this interface. For PIX/ASA devices running operating system 7.2(2)18 or earlier, valid VLAN IDs are 1 to 1001; with version 7.2(2)19 or later, valid IDs are 1 to 4090. For Catalyst 6500 services modules, valid IDs are 1 to 4096. The specified VLAN ID must not be in use on any connected device. Some VLAN IDs might be reserved on connected switches; see the switch documentation for more information. In multiple-context mode, you can only set the VLAN ID in the system configuration. See Configuring Subinterfaces (PIX/ASA) for more information. |
Subinterface ID |
When Subinterface is the chosen interface Type, or when defining an interface on a device operating in transparent mode, provide an integer between 1 and 4294967293 as the Subinterface ID. For subinterface port identification, this ID is appended to the chosen Hardware Port. For example, GigabitEthernet0.4 represents the subinterface assigned an ID of 4, operating on the port GigabitEthernet0. Note You cannot change the Subinterface ID after you set it. |
Route Map |
Select the Route Map from the Route Map Object Selector dialog box. Note Except VNI Interface, all other interface types support Policy Based Routing for ASA devices running the software version 9.4(1) or higher. VNI Interface supports Policy Based Routing for ASA devices running the software version 9.5(1) or higher. |
IP Type |
PIX 7.0+ and ASA (except the 5505 in transparent mode) only. The IP Type defines the type of IP addressing used for the interface; choose Static IP, Use DHCP, or PPPoE (as described in Device Interface: IP Type (PIX/ASA 7.0+)). Note You can configure DHCP and PPPoE only on the outside interface of a security appliance. |
IP Address Subnet Mask |
Catalyst 6500 services modules (ASA-SMs and FWSMs) in routed mode only. Use these two fields to assign an IP address and subnet mask to the VLAN interface. The IP address must be unique for each interface. The Subnet Mask can be expressed in dotted decimal format (for example, 255.255.255.0), or by entering the number of bits in the network mask (for example, 24). Till Version 4.12, 255.255.255.254 and 255.255.255.255 were not to be used for an interface connected to the network because it would stop traffic on that interface. Beginning from Version 4.13, /31 subnet mask (or 2555.2555.255.254) is supported for a point to point interface connected to the network. Cisco Security Manager displays a warning message on saving the interface record. If you omit the Subnet Mask value, a “classful” network is assumed, as follows:
- The Class A netmask (255.0.0.0) is assumed if the first octet of the IP Address is 1 through 126 (that is, addresses 1.0.0.0 through 126.255.255.255).
- Subnet Mask
The Class B netmask (255.255.0.0) is assumed if the first octet of the IP Address is 128 through 191 (that is, addresses 128.0.0.0 through 191.255.255.255).
- The Class C netmask (255.255.255.0) is assumed if the first octet of the IP Address is 192 through 223 (that is, addresses 192.0.0.0 through 223.255.255.255).
Note Do not use addresses previously used for routers, hosts, or any other firewall device commands, such as an IP address in the global pool or a static NAT entry. |
Description |
You can enter an optional description of up to 240 characters on a single line, without carriage returns. In multiple-context mode, the system description is independent of the context description. For a failover or state link, the description is fixed as “LAN Failover Interface,” “STATE Failover Interface,” or “LAN/STATE Failover Interface,” for example. You cannot edit this description. The fixed description overwrites any description you enter here if you make this interface a failover or state link. |
Redundant Interface; these options not available on ASA 5505 devices or Catalyst 6500 services modules (ASA-SMs and FWSMs).
|
Redundant ID |
When Redundant Interface is the chosen interface Type, provide an identifier for this redundant interface; valid IDs are the integers from 1 to 8. See Configuring Redundant Interfaces for more information. |
Primary Interface Secondary Interface |
When Redundant Interface is the chosen interface Type, choose the primary member of the redundant interface pair from the Primary Interface list of available interfaces. Available interfaces are presented by Hardware Port IDs, as named interfaces cannot be used for a redundant interface pair. Similarly, choose the secondary member of the redundant interface pair from the Secondary Interface list of available interfaces. Note Member interfaces must be enabled and of the same type (e.g., GigabitEthernet), and cannot have a Name, IP Address, or Security Level assigned. In fact, do not configure any options other than Duplex and Speed on the member interfaces. |
These options available on ASA 5505 devices only.
|
Block Traffic To |
Restricts this VLAN interface from initiating contact with the VLAN chosen here. |
Backup Interface |
Choose a VLAN interface as a backup interface, for example, to an ISP. The backup interface does not pass traffic unless the default route through the primary interface fails. To ensure that traffic can pass over the backup interface, be sure to configure default routes on both the primary and backup interfaces so that the backup interface can be used when the primary fails. |
Active MAC Address Standby MAC Address |
Use the Active MAC Address field to manually assign a private MAC address to the interface; the Standby MAC Address field can be used to set a standby MAC address for use with device-level failover. Refer to Device Interface: MAC Address for more information about these fields. |
EtherChannel Interface options; available on ASA 8.4.1+ devices only.
|
EtherChannel ID |
When EtherChannel is the chosen interface Type, enter an identifier for this EtherChannel (also referred to as a “port-channel”). Valid values are 1 to 48—you can define up to 48 port-channel groups. See Configuring EtherChannels, for more information. |
Available Interfaces/Members in Group |
When EtherChannel is the chosen interface Type, you can assign interfaces to this EtherChannel group by selecting them in the Available Interfaces list and then clicking the >> button to add them to the members list to the right. You can assign up to 16 interfaces to a channel group. For ASA 9.2(1) and later, each channel group can have up to 16 active interfaces. For switches that support only eight active interfaces and for ASA versions earlier than 9.2(1), only eight interfaces can be active, the remaining interfaces can act as standby links in case of interface failure. Alternatively, you can create a static EtherChannel by setting LACP Mode to On (on the Advanced tab, see Add/Edit Interface Dialog Box: Advanced Tab (ASA/PIX 7.0+)), which means all interfaces in the group can pass traffic. Note All interfaces in the channel group must be the same type and speed. The first interface added to the channel group determines the type and speed for the group. See Configuring EtherChannels, for more information. |
Add/Edit Interface Dialog Box: Cisco Firepower 9000 (General and Advanced tabs)
For the elements supported in Cisco Firepower 9000 devices for the General and Advanced tabs, see the Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM). In addition, the following changes are applicable only to Cisco Firepower 9000 devices.
Table 46-9 Add/Edit Interface Dialog Box Cisco Firepower 9000
|
|
Type |
Choose the type of interface. Redundant Interfaces are not supported in Cisco Firepower 9000 devices. |
Management Only Individual |
Applicable only in Cisco Firepower 9000 devices and only if the device is in cluster mode.
Note You cannot enable both Management Only and Management Only Individual check boxes at the same time. You can configure Cluster pool only when Management Only Individual check box is selected.
|
Name |
Provide an interface name up to 48 characters in length. The Name should be a memorable name for the interface that relates to its use. The Interface name must begin with “Ethernet” and must have the following format: Ethernet[slot]/[port]/sub-port, where,
- slot is between 1 and 3
- port is between 1 and 8
- sub-port is between 1 and 4
- sub-port is not applicable for slot 1
|
The following elements are not supported in Cisco Firepower 9000 devices: |
Media Type (General Tab) |
Duplex(Advanced Tab) |
Speed (Advanced Tab) |
Available Interfaces/Members in Group (General Tab) |
Load Balancing (Advanced Tab) |
LACP Mode (Advanced Tab) |
VSS or vPC Switch ID (Advanced Tab) |
Active Physical Interfaces (Advanced Tab) |
Span EtherChannel across the ASA Cluster (Advanced Tab) |
Enable load balancing between switch pairs in VSS or vPC mode (Advanced Tab) |
Member Interface Configuration (Advanced Tab) |
Add/Edit Interface Dialog Box: Advanced Tab (ASA/PIX 7.0+)
The Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM), is used to define and configure interfaces, subinterfaces, redundant, and EtherChannel interfaces on ASA and PIX 7.0+ devices. You can access the Add/Edit Interface dialog box from the Interfaces page. See Managing Device Interfaces, Hardware Ports, and Bridge Groups for more information.
The Advanced panel of this dialog box is used to configure basic interface settings, including Duplex, Speed, and maximum transmission unit (MTU) parameters, as described in the following table.
Related Topics
Table 46-10 Advanced tab: Add/Edit Interface Dialog Box (ASA/PIX 7.0+)
|
|
Duplex |
Lists the duplex options for the interface, including Auto, Full, Half, or N/A, depending on the interface type. For TenGigabitEthernet (ASA 5580 only), Duplex is automatically set to Full. Note This option is not available when Subinterface or Redundant is the chosen Interface type. |
Speed |
Lists the speed options (in bits per second) for a physical interface; not applicable to logical interfaces. The speeds available depend on the interface type.
- auto
- 10
- 100
- 1000
- 10000 (set automatically for a TenGigabitEthernet interface; available only on ASA 5580)
- nonegotiate
Note This option is not available when Subinterface or Redundant is the chosen Interface type. |
MTU |
Specify the maximum packet size in bytes; that is, the maximum transmission unit (MTU). The value depends on the type of network connected to the interface. Valid values are 300 to 65535 bytes. Default is 1500 for all types except PPPoE, for which the default is 1492. In multiple-context mode, set the MTU in the context configuration. |
Active MAC Address Standby MAC Address |
Available only on PIX 7.2+ and ASA 7.2+ devices. Use the Active MAC Address field to manually assign a private MAC address to the interface; the Standby MAC Address field can be used to set a standby MAC address for use with device-level failover. Refer to Device Interface: MAC Address for more information about these fields. |
Roles |
All interface roles assigned to this interface are listed in this field. Role assignments are based on pattern matching between the Name given to this interface and all currently defined Interface Role objects in Cisco Security Manager. Interface role objects are replaced with the actual interface IP addresses when the configuration is generated for each device. They allow you to define generic rules—ones that can apply to multiple interfaces. For more information on roles and how to define and use them, see Understanding Interface Role Objects. |
MAC Address |
Site specific MAC address. |
Site ID |
Site ID to specify the site the current unit belongs to. |
Beginning with Security Manager version 4.9 for ASA devices running the software version 9.5(1) or higher, you can use inter-site clustering for Spanned EtherChannels in routed mode. To avoid MAC address flapping, configure a site ID for each cluster member so that a site-specific MAC address for each interface can be shared among a site’s units. |
EtherChannel Interface options; available on ASA 8.4.1+ devices only. |
Load Balancing |
When EtherChannel is the chosen interface Type (on the General panel), choose a load-balancing method for the channel links. See About EtherChannel Load Balancing, for more information about this option. |
LACP Mode |
Select the desired LACP Mode ; the default is Active, which means up to eight interfaces are active, while up to eight are in stand-by mode, as determined by the Minimum and Maximum values under Active Physical Interfaces. If you select On, a static port-channel is created in which all member interfaces are all “on,” meaning you can have up to 16 ports passing traffic, with no stand-by ports. When you select this option, the Mode for all interfaces assigned to this EtherChannel group is switched to On (if the Mode for each is not already On). See Editing LACP Parameters for an Interface Assigned to an EtherChannel, for more information about this mode. |
Active Physical Interfaces |
When EtherChannel is the chosen interface Type (on the General panel), specify the minimum and maximum number of interfaces that can be active for this EtherChannel group:
- Minimum – Specify the minimum number of active interfaces for this group. For ASA 9.2(1)+, you can specify a value from 1 to 16; for earlier versions, enter a value from 1 to 8.
If the active interfaces in the channel group falls below this value, then the port-channel interface goes down, and could trigger a device-level failover.
- Maximum – Specify the maximum number of interfaces that can be active. For ASA 9.2(1)+, you can specify a value from 1 to 16; for earlier versions, enter a value from 1 to 8.
For 16 active interfaces, be sure that your switch supports the feature (for example, the Cisco Nexus 7000 with F2-Series 10 Gigabit Ethernet Module). If your switch does not support 16 active interfaces, be sure to set this command to 8 or fewer. Interfaces available to the channel are selected on the General tab of this dialog box (Add/Edit Interface Dialog Box: General Tab (PIX 7.0+/ASA/FWSM)). Specifying 3, 5, 6, or 7 active ports in an EtherChannel bundle provides poor load balancing, because some ports get up to twice the load of others. We recommend specifying 2, 4, or 8 active ports per EtherChannel to achieve effective load balancing. (A value of 1 provides no load balancing at all.) |
DHCP Relay options; available on ASA-SM 9.1.2+ devices only. |
DHCP Relay Servers |
Enter the IP address or select a Networks/Hosts object representing the interface-specific DHCP server to which DHCP requests on this interface are relayed. Use a comma to separate multiple values. You can configure a maximum of 4 interface-specific DHCP relay servers and a maximum of 10 global and interface-specific DHCP relay servers combined. Note IPv6 is not supported for interface-specific servers. When a DHCP request enters an interface, the DHCP servers to which the ASA relays the request depends on your configuration. You can configure the following types of servers:
- Interface-specific DHCP servers—When a DHCP request enters a particular interface, then the ASA relays the request only to the interface-specific servers.
- Global DHCP servers—When a DHCP request enters an interface that does not have interface-specific servers configured, the ASA relays the request to all global servers. If the interface has interface-specific servers, then the global servers are not used. For more information, see DHCP Relay Page.
|
DHCP Relay Trust Info (Option 82) |
Specifies that you want to trust this DHCP client interface. You can configure interfaces as trusted interfaces to preserve DHCP Option 82. Note You can also trust all DHCP client interfaces. For more information, see DHCP Relay Page. DHCP Option 82 is used by downstream switches and routers for DHCP snooping and IP Source Guard. Normally, if the ASA DHCP relay agent receives a DHCP packet with Option 82 already set, but the giaddr field (which specifies the DHCP relay agent address that is set by the relay agent before it forwards the packet to the server) is set to 0, then the ASA will drop that packet by default. You can now preserve Option 82 and forward the packet by identifying an interface as a trusted interface. |
Secure Group Tagging options; available on ASA 9.3.1+ devices only. SGT plus Ethernet Tagging, also called Layer 2 SGT Imposition, enables the ASA to send and receive security group tags on Ethernet interfaces using Cisco proprietary Ethernet framing (EtherType 0x8909), which allows the insertion of source security group tags into plain-text Ethernet frames. The ASA inserts security group tags on the outgoing packet and processes security group tags on the incoming packet, based on a manual per-interface configuration. This feature allows inline hop-by-hop propagation of endpoint identity across network devices and provides seamless Layer 2 SGT Imposition between each hop. Note Supported only on physical interfaces, VLAN interfaces, port channel interfaces, and redundant interfaces. Not supported on logical interfaces or virtual interfaces, such as BVI, TVI, and VNI.
Does not support failover links or cluster control links. |
Enable secure group tagging for Cisco TrustSec |
Enables SGT plus Ethernet Tagging (also called Layer 2 SGT Imposition). |
Tag egress packets with secure group tags |
Enables propagation of a security group tag (called sgt) on an interface. |
Assign a static secure group tag to all ingress packets |
Applies a static security group tag to incoming traffic from the peer. If enabled, you must specify the SGT number to use in the Secure Group Tag field. |
Secure Group Tag |
Specifies the SGT number to apply to incoming traffic from the peer. Valid values are from 2-65519. |
Trusted Interface |
Indicates that ingress traffic on the interface should not have its existing SGT overwritten with the static SGT specified. |
ASA Cluster (Layer 3); available on ASA 5580 and 5585 devices in cluster mode only. Supported by all interfaces when ASA cluster is in Router mode and supported by management interface when ASA cluster is in Transparent mode. |
IPv4 Address Pool |
Enter or select the IPv4 Pool object that represents the pool of addresses to use. |
MAC Address Pool |
Enter or select the MAC Pool object that represents the pool of MAC addresses to use. |
ASA Cluster (Layer 2); available on ASA 5580 and 5585 devices in cluster mode only. Supported on EtherChannel interfaces for ASA clusters. Not supported on Management interface when ASA cluster is in Transparent mode. |
Span EtherChannel across the ASA Cluster |
Select to configure an EtherChannel that spans all ASAs in the cluster, and provides load balancing as part of the EtherChannel operation. |
Enable load balancing between switch pairs in VSS or vPC mode |
(Optional) If you are connecting the ASA to two switches in a Virtual Switching System (VSS) or Virtual Port Channel (vPC), then you should enable load balancing by checking the Enable load balancing between switch pairs in VSS or vPC mode check box. This feature ensures that the physical link connections between the ASAs to the VSS (or vPC) pair are balanced. |
Member Interface Configuration |
Identifies the LACP mode for the interface and the Virtual Switching System (VSS) or Virtual Port Channel (vPC) switch to which a given interface is connected, 1 or 2. |
Advanced tab options specific to ASA 5505 devices (routed mode only)
|
Block Traffic To |
Restricts this VLAN interface from initiating contact with the VLAN chosen here. |
Backup Interface |
Choose a VLAN interface as a backup interface, for example, to an ISP. The backup interface does not pass traffic unless the default route through the primary interface fails. To ensure that traffic can pass over the backup interface, be sure to configure default routes on both the primary and backup interfaces so that the backup interface can be used when the primary fails. |
Advanced tab options specific to FWSM 3.1+ devices
|
Bridge Group |
For an FWSM 3.1+ operating in transparent mode, this read-only field indicates the Bridge group to which this interface is assigned. See Add/Edit Bridge Group Dialog Box for more information. |
ASR Group |
To add this interface to an asymmetric routing group, enter the ASR group number in this field. Stateful failover must be enabled for asymmetric routing support to function properly between units in failover configurations. Valid values for ASR group range from 1 to 32. See About Asymmetric Routing Groups for more information. |
Pause Frame for Flow Control options When a network interface gets over loaded, flow control allows it to send PAUSE requests to the devices sending it data to allow the over loaded condition to clear. If flow control is not enabled and an over loaded condition occurs, the device will drop packets. When the receiving part of the interface reaches the high water mark, the transmitting part of the interface starts to generate pause frames. The remote device is expected to stop / reduce the transmission of packets for the pause time mentioned in the pause frame. If the receiving part of the interface is able to clear its queue or reaches the low water mark within the pause time, the transmitting part of the interface sends out a special pause frame that mentions the pause time as zero.This enables the remote device to start to transmit packets. If the receiving part of the interface still works on the queue, once the pause time expires, the transmitting part of the interface sends a new pause frame again with a new pause time. Note Pause Frame for flow control is supported only on physical interfaces on ASA 8.2 and above, in the single and multi-context mode. It is not supported on logical interfaces or virtual interfaces, such as BVI, TVI, and VNI. |
Enable Pause Frame |
(Optional) Enables transmission of pause frame for flow control. |
Use Default Values |
(Optional) Uses default values for Low Watermark, High Watermark and Pause Time, based on the device. If this is unchecked, specify the values as per the Device specific Pause Frame Flow Control values reference table. |
Low Watermark (in Kilobytes) |
Enter a value for the low-water mark. After the interface sends a pause frame, when the buffer usage is reduced below the low-water mark, the interface sends an “transmission on’ frame. The remote device can resume transmitting data. |
High Watermark (in Kilobytes) |
Enter a value for the high-water mark.When the buffer usage exceeds the high-water mark, the interface sends a pause frame. |
Pause Time |
Enter a value for the pause refresh threshold value, between 0 and 65535 slots. Each slot is the amount of time to transmit 64 bytes, so the time per unit depends on your link speed. The remote device can resume traffic after receiving an transmission on frame, or after the transmission off frame expires, as controlled by this timer value in the pause frame. If the buffer usage is consistently above the high-water mark, pause frames are sent repeatedly, controlled by the pause refresh threshold value. |
Table 46-11 Device specific Pause Frame Flow Control values
|
Low Watermark Range
(in Kb)
|
Default Low Watermark (in Kb)
|
High Watermark Range
(in Kb)
|
Deafult High Watermark
(in Kb)
|
|
|
ASA 5515 |
0-20 |
8 |
0-20 |
16 |
0-65535 |
26624 |
ASA 5525 |
0-20 |
8 |
0-20 |
16 |
0-65535 |
26624 |
ASA 5545 |
0-20 |
8 |
0-20 |
16 |
0-65535 |
26624 |
ASA 5510 |
0-48 |
16 |
0-48 |
24 |
0-65535 |
26624 |
ASA 5585 |
Values are not supported; only “flowcontrol send on” is supported. |
ASA 5506 |
1-25 |
3 |
1-25 |
8 |
1-65535 |
18432 |
ISA-3000-2C2F |
0-64 |
27 |
0-64 |
34 |
0-65535 |
26624 |
ISA-3000-4C |
0-64 |
27 |
0-64 |
34 |
0-65535 |
26624 |
1783-SAD4T0S |
0-64 |
27 |
0-64 |
34 |
0-65535 |
26624 |
Configuring IPv6 Interfaces (ASA/FWSM)
When Interface, Subinterface, Redundant, or EtherChannel is the chosen Type in the Add Interface or Edit Interface dialog box, the dialog box presents three tabbed panels of options: General, Advanced and IPv6. The options provided by the IPv6 panel are described in this section.
Note
These options are available only on ASA 7.0+ devices in routed mode; ASA 8.2+ devices in transparent mode; and FWSM 3.1+ devices in routed mode.
Navigation Path
You can access the IPv6 panel in the Add Interface and Edit Interface dialog boxes, which are accessed from the ASA or FWSM Interfaces page, as described in Managing Device Interfaces, Hardware Ports, and Bridge Groups.
Related Topics
Field Reference
Table 46-12 IPv6 tab: Add/Edit Interface Dialog Box (ASA/FWSM)
|
|
Enable IPv6 |
Check this box to enable IPv6 and configure IPv6 addresses on this interface. You can deselect this option to disable IPv6 on the interface, but retain the configuration information. |
Enforce EUI-64 |
When selected, use of Modified EUI-64 format interface identifiers in IPv6 addresses on a local link is enforced. When this option is enabled on an interface, the source addresses of IPv6 packets received on the interface are verified against the source MAC addresses to ensure that the interface identifiers use the Modified EUI-64 format. If the interface identifier in an IPv6 packet is not in the Modified EUI-64 format, the packet is dropped and the following system log message is generated: %PIX|ASA-3-325003: EUI-64 source address check failed. Address format verification is performed only when a flow is created. Packets from an existing flow are not checked. Additionally, address verification can be performed only for hosts on the local link. Packets received from hosts behind a router will fail the address format verification, and be dropped, because their source MAC address will be the router MAC address and not the host MAC address. The Modified EUI-64 format interface identifier is derived from the 48-bit link-layer (MAC) address by inserting the hex number FFFE between the upper three bytes (OUI field) and the lower 3 bytes (serial number) of the link-layer address. To ensure the chosen address is from a unique Ethernet MAC address, the next-to-lowest order bit in the high-order byte is inverted (universal/local bit) to indicate the uniqueness of the 48-bit address. For example, an interface with a MAC address of 00E0.B601.3B7A would have a 64-bit interface ID of 02E0:B6FF:FE01:3B7A. |
DAD Attempts |
To specify the number of consecutive neighbor solicitation messages that are sent on an interface during duplicate address detection (DAD), enter a number from 0 to 600 in this field. Entering 0 disables duplicate address detection on the interface. Entering 1 configures a single transmission without follow-up transmissions; this is the default. Duplicate address detection verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection uses neighbor solicitation messages to verify the uniqueness of unicast IPv6 addresses. When duplicate address detection identifies a duplicate address, the state of the address is set to DUPLICATE and the address is not used. If the duplicate address is the link-local address of the interface, the processing of IPv6 packets is disabled on the interface and an error message similar to the following is issued: %PIX-4-DUPLICATE: Duplicate address FE80::1 on outside If the duplicate address is a global address of the interface, the address is not used and an error message is issued, similar to that shown previously for a duplicate link-local address. All configuration commands associated with the duplicate address remain as-configured while the state of the address is set to DUPLICATE. If the link-local address for an interface changes, duplicate address detection is performed on the new link-local address, and all other IPv6 address associated with the interface are regenerated (that is, duplicate address detection is performed only on the new link-local address). |
NS Interval |
The interval between IPv6 neighbor solicitation retransmissions, in milliseconds. Valid values range from 1000 to 3600000 milliseconds; the default value is 1000 milliseconds. Note This value is included in all IPv6 router advertisements sent out on this interface. |
Reachable Time |
The amount of time, in milliseconds, within which a remote IPv6 node is considered still reachable, after initial reachability was confirmed. Valid values range from 0 to 3600000 milliseconds, the default value is 0. When 0 is used for the value, the reachable time is set as undetermined—it is up to the receiving devices to set and track reachable time. A configured time enables detection of unavailable neighbors. A shorter time allows detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation. |
Managed Config Flag |
Whether or not to set the flag "managed-config-flag" in the IPv6 router advertisement packet. |
Other Config Flag |
Whether or not to set the flag "other-config-flag" in the IPv6 router advertisement packet. |
Enable RA |
When checked, IPv6 router advertisement transmissions are enabled on the interface. The following options are enabled:
- RA Lifetime – The “router lifetime” value specifies how long nodes on the local link should consider the security appliance as the default router on the link. Valid values range from 0 to 9000 seconds; the default is 1800 seconds. Entering 0 indicates that the security appliance should not be considered a default router on the selected interface.
Any non-zero value should not be less than the following RA Interval value. Note This value is included in all IPv6 router advertisements sent out on this interface.
- RA Interval – The interval between IPv6 router advertisement transmissions on this interface. Valid values range from 3 to 1800 seconds, (or from 500 to 1800000 milliseconds if the following RA Interval in Milliseconds option is checked); the default is 200 seconds.
The interval between transmissions should be less than or equal to the RA Lifetime value if it is non-zero. To prevent synchronization with other IPv6 nodes, randomly adjust the actual value used to within 20 percent of the desired value.
- RA Interval in Milliseconds – Checking this option indicates that the provided RA Interval value is in milliseconds, rather than seconds.
|
Interface IPv6 Addresses |
The IPv6 addresses assigned to the interface are specified in this section of the dialog box.
- Link-Local Address – To override the link-local address that is automatically generated for the interface, enter the desired IPv6 link-local address in this field.
The link-local address is composed of the link-local prefix FE80::/64 and the interface ID in Modified EUI-64 format. For example, an interface with a MAC address of 00E0.B601.3B7A would have a link-local address of FE80::2E0:B6FF:FE01:3B7A. An error will occur if another host is using the specified address.
- Enable Address Auto-Configuration – Select this option to enable automatic configuration of IPv6 addresses on the interface using stateless autoconfiguration. The addresses are configured based on the prefixes received in Router Advertisement (RA) messages. If a link-local address has not been configured, then one is automatically generated for this interface. An error occurs if another host is already using the generated link-local address.
– Trust the DHCP Servers for default gateway – Select this radio button to install a default route from Router Advertisements that come from a trusted source - the directly-connected network. – Ignore trust and accept router advertisements – Select this radio button to install a default route from Router Advertisements that come from another network.
- The table in this section displays the IPv6 addresses assigned to this interface. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.)
Add Row and Edit Row open the IPv6 Address for Interface Dialog Box. |
Interface IPv6 Prefixes |
Use the table in this section to configure which IPv6 prefixes (that is, the network portion of the IPv6 addresses) are included in IPv6 router advertisements. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.) Add Row and Edit Row open the IPv6 Prefix Editor Dialog Box. |
Interface IPv6 DHCP |
Use this section to enable the DHCPv6 Prefix Delegation client on one or more interfaces. The ASA obtains one or more IPv6 prefixes that it can subnet and assign to inside networks. Typically, the interface on which you enable the prefix delegation client obtains its IP address using the DHCPv6 address client; only other ASA interfaces use addresses derived from the delegated prefix. Select one of the following:
- Server Pool – Select this to configure the IPv6 DHCP pool that contains the information you want the DHCPv6 server to provide. You can configure separate pools for each interface if you want, or you can use the same pool on multiple interfaces. Use the Add Row and Edit Row buttons in the DHCP Pool Selector dialog to manage these entries. (These are standard buttons, as described in Using Tables.)
Add Row and Edit Row open the Add or Edit DHCPv6 Pool Dialog Box.
OR
- Client Prefix Delegation Name – Enable the DHCPv6 Prefix Delegation client by entering a name for the prefix(es) obtained on this interface. Valid values are a string not exceeding 200 characters.
– DHCPv6 Prefix Hint – Use the Add Row button to provide one or more hints about the delegated prefix that you want to receive. Typically you want to request a particular prefix length, such as ::/60, or if you have received a particular prefix before and want to ensure you get it again when the lease expires, you can enter the whole prefix as the hint. If you enter multiple hints (different prefixes or lengths), then it is up to the DHCP server which hint to honor, or whether to honor the hint at all. Note If the prefix suggested as the hint is a valid prefix in the associated local prefix pool and is not assigned elsewhere, the server delegates the client-suggested prefix. Otherwise, the hint is ignored and a prefix is delegated from the free list in the pool. – Enable DHCP – Select this to obtain an address using DHCPv6. Optionally, select Enable Default Route to obtain a default route from Router Advertisements. |
Note If a DHCPv6 client or Server Pool is configured on an IPv6 Interface, the same interface cannot be used to configure DHCPv6 Relay. |
IPv6 Address for Interface Dialog Box
This dialog box is used to add or edit an IPv6 address assigned to an ASA or FWSM interface. Multiple IPv6 addresses can be assigned to the interface in the IPv6 panel of the Add Interface or Edit Interface dialog box.
Note
This dialog box is available only on ASA 7.0+ devices in routed mode; ASA 8.2+ devices in transparent mode; and FWSM 3.1+ devices in routed mode.
Navigation Path
You can access the IPv6 Address for Interface dialog box:
- From the IPv6 panel of the ASA or FWSM Add Interface and Edit Interface dialog boxes.
- From the Management IPv6 page of an ASA 5505 in transparent firewall mode (version 8.2 and 8.3 devices only).
Click the Add Row or Edit Row buttons beneath the table in the Interfaces IPv6 Addresses section to open the dialog box.
Related Topics
Field Reference
Table 46-13 IPv6 Address for Interface Dialog Box
|
|
Prefix Name |
(Optional) Enter a prefix name to use a delegated prefix. Valid values are a string not exceeding 200 characters.
Tip ‘DHCP’ is a reserved word; Cisco Security Manager will not accept it as Prefix Name.
Note Make sure that the DHCPv6 Prefix Delegation Client is enabled on this ASA Interface. For more information, see the Interface IPv6 DHCP element in the IPv6 tab: Add/Edit Interface Dialog Box (ASA/FWSM)> |
Address/Prefix Length |
Enter an IPv6 network address to be assigned to the interface, with its Prefix Length appended, where the Prefix Length integer indicates how many of the high-order, contiguous bits of the address comprise network portion of the address. A slash (/) must precede the Prefix Length. For example, 3FFE:C00:0:1::/64. Typically, the delegated prefix will be /60 or smaller so you can subnet to multiple /64 networks. /64 is the supported subnet length if you want to support SLAAC for connected clients. You should specify an address that completes the /60 subnet, for example ::1:0:0:0:1. Enter :: before the address in case the prefix is smaller than /60. For example, if the delegated prefix is 2001:DB8:1234:5670::/60, then the global IP address assigned to this interface is 2001:DB8:1234:5671::1/64. The prefix that is advertised in router advertisements is 2001:DB8:1234:5671::/64. In this example, if the prefix is smaller than /60, the remaining bits of the prefix will be 0's as indicated by the leading ::. For example, if the prefix is 2001:DB8:1234::/48, then the IPv6 address will be 2001:DB8:1234::1:0:0:0:1/64. |
EUI-64 |
If this box is checked, the EUI-64 interface ID will be used in the low-order 64 bits of the IPv6 address. If the value specified for the Prefix Length is greater than 64 bits, the prefix bits have precedence over the interface ID. An error occurs if another host is using the specified address. The Modified EUI-64 format interface ID is derived from the 48-bit link-layer (MAC) address by inserting the hex number FFFE between the upper three bytes (OUI field) and the lower 3 bytes (serial number) of the link layer address. To ensure the chosen address is from a unique Ethernet MAC address, the next-to-lowest order bit in the high-order byte is inverted (universal/local bit) to indicate the uniqueness of the 48-bit address. For example, an interface with a MAC address of 00E0.B601.3B7A would have a 64 bit interface ID of 02E0:B6FF:FE01:3B7A. |
IPv6 Address Pool |
Enter or select the IPv6 Pool object that represents the pool of addresses to use. |
IPv6 Prefix Editor Dialog Box
This dialog box is used to add or edit an IPv6 prefix (that is, the network portion of an IPv6 address), providing control over individual parameters, including whether the prefix should be included in IPv6 router advertisements. Multiple prefixes can be configured in the IPv6 panel of the ASA or FWSM Add Interface or Edit Interface dialog box.
Note
This dialog box is available only on ASA 7.0+ devices in routed mode; ASA 8.2+ devices in transparent mode; and FWSM 3.1+ devices in routed mode.
By default, prefixes configured as addresses on an interface are advertised in router advertisements. If you configure specific prefixes for advertisement, then only those prefixes are advertised. The valid and preferred lifetimes are counted down in real time. Alternately, a date can be set to specify the expiration of a prefix. When the expiration is reached, the prefix is no longer advertised.
Navigation Path
You can access the IPv6 Prefix Editor dialog box from the IPv6 panel of the Add Interface and Edit Interface dialog boxes: click the Add Row or Edit Row buttons beneath the table in the Interfaces IPv6 Prefixes section in either of those dialog boxes.
Related Topics
Field Reference
Table 46-14 IPv6 Prefix Editor Dialog Box
|
|
Address/Prefix Length |
Enter an IPv6 network address, with its Prefix Length appended, where the Prefix Length integer indicates how many of the high-order, contiguous bits of the address represent the network portion of the address. A slash (/) must precede the Prefix Length. For example, 3FFE:C00:0:1::/64. |
Default |
If this box is checked, the settings in this dialog box will apply to all prefixes, rather than a single address. (When checked, the Address/Prefix Length field is disabled.) |
No Advertisements |
When checked, hosts on the local link cannot use the specified prefix in advertisements. |
Off Link |
When checked, the specified prefix is “off-link”; that is, not locally reachable on the link. When on-link (the default), the specified prefix is assigned to the link. Nodes sending traffic to addresses that contain the specified prefix consider the destination to be locally reachable on the link. |
No Auto-Configuration |
When checked, hosts on the local link cannot use the specified prefix for IPv6 autoconfiguration. When auto-configuration is on (the default), hosts on the local link can use the specified prefix for IPv6 autoconfiguration. |
Prefix Lifetime |
You can expand this section of the dialog box to display the following expiration options:
- Lifetime Duration – Select this option to define prefix expiration as a length of time; the following options are enabled:
– Valid Lifetime – The amount of time (in seconds) that the specified IPv6 prefix is advertised as being valid. Enter a value from 0 to 4294967295 seconds. The maximum value represents infinity (that is, the lifetime does not expire), which can also be specified by the checking the Infinite box. The default is 2592000 (30 days). – Preferred Lifetime – The amount of time (in seconds) that the specified IPv6 prefix is advertised as being preferred. Enter a value from 0 to 4294967295 seconds. The maximum value represents infinity (that is, the lifetime does not expire), which can also be specified by the checking the Infinite box. The default is 604800 (7 days). The Preferred Lifetime must be less than or equal to the Valid Lifetime.
- Lifetime Expiration Date – Select this option to define prefix expiration as a specific date. Note that acceptable values for this date can range from today’s date to one year from today’s date. The following options are enabled:
– Valid – The prefix is advertised as being valid until this date and time are reached. Enter a date in the form Mmm dd yyyy (that is, three-letter month abbreviation, two-digit date, and four-digit year), or click the calendar icon to select a date from a scrolling calendar. Also, enter the time of expiration on the specified date, in the form hh:mm , based on a 24-hour clock. – Preferred – The prefix is advertised as being preferred until this date and time are reached. Enter a date in the form Mmm dd yyyy (that is, three-letter month abbreviation, two-digit date, and four-digit year), or click the calendar icon to select a date from a scrolling calendar. Also, enter the time of expiration on the specified date, in the form hh:mm , based on a 24-hour clock. The Preferred date and time must be earlier than or equal to the Valid date and time. |
Add or Edit DHCPv6 Pool Dialog Box
This dialog box is used to add or edit the DHCPv6 Server Pool. For clients that use StateLess Address Auto Configuration (SLAAC) in conjunction with the Prefix Delegation feature, you can configure the ASA to provide information such as the DNS server or domain name when they send Information Request (IR) packets to the ASA. The ASA only accepts IR packets, and does not assign addresses to the clients.
Navigation Path
- Choose Policy Objects from the Manage menu, or click the Policy Object Manager button in the button bar, to open the Policy Object Manager pane in the lower section of the Configuration Manager window. Select Pool Objects > DHCPv6 Pool Object from the Object Type Selector. Right-click inside the work area and select New Object (and select an object type), or right-click a row and select Edit Object ; you also can use the related buttons at the bottom of the pane to open either dialog box.
OR
- You can access the Add DHCPv6 Pool dialog box from DHCPv6 Pool Selector dialog box: click the Add Row or Edit Row buttons beneath the Available DHCPv6 Pool table. The DHCPv6 Pool Selector dialog box can been accessed from the Server Pool radio button in the Interface IPv6 DHCP section of the IPv6 panel of the Add Interface and Edit Interface dialog box.
Related Topics
Field Reference
Table 46-15 Add DHCPv6 Pool Dialog Box
|
|
Name |
The DHCPv6 Pool name should not exceed 200 characters. Object names are not case-sensitive. |
- Configure parameters on one or more tabs, to provide responses to IR messages to clients.
- For each of these tabs, specify the following as appropriate:
– DNS/SIP/ NIS/ NISP/ SNTP Server: Enter a server name. Make sure that the IPv6 addresses are in the correct format. For more information on IPv6 address format, see http://www.ietf.org/rfc/rfc2373.txt. – DNS/ SIP/NIS/NISP Domain Name: Enter a domain name. Domain names must begin and end with a digit/letter, only letters, digits and hyphen are allowed as internal characters, labels are separated by a dot.Each label must be up to 63 characters and the entire host name has a maximum of 255 characters. For more information on domain names format, see http://www.ietf.org/rfc/rfc1123.txt. Note The import command uses one or more parameters that the ASA obtained from the DHCPv6 server on the Prefix Delegation client interface. You can mix and match manually-configured parameters with imported parameters; however, you cannot configure the same parameter manually and in the import command. |
Server tab |
(Optional) Specify DNS Server Name and Domain Name. |
SIP tab |
(Optional) Specify SIP Server Name and SIP Domain Name. |
NIS tab |
(Optional) Specify NIS Server Name and NIS Domain Name. |
NISP tab |
(Optional) Specify NISP Server Name and NISP Domain Name. |
SNTP tab |
(Optional) Specify SNTP Server Name. |
Category |
The category assigned to the object. Categories help you organize and identify rules and objects. See Using Category Objects. |
Allow Value Override per Device Overrides Edit button |
Whether to allow the object definition to be changed at the device level. For more information, see Allowing a Policy Object to Be Overridden and Understanding Policy Object Overrides for Individual Devices. If you allow device overrides, you can click the Edit button to create, edit, and view the overrides. The Overrides field indicates the number of devices that have overrides for this object. |
Device Interface: IP Type (PIX/ASA 7.0+)
A security device operating in single-context, routed mode requires IP addressing for its interfaces; however, firewall interfaces do not have IP addresses until you assign them. Note that in transparent mode, the device acts as an access-control bridge (a “bump in the wire”)—you assign different VLANs to each interface, but IP addressing is not necessary.
The Add/Edit Interface dialog box presented for an independent ASA or PIX 7.0+ device in single-context, routed mode includes the section IP Type, where you specify the type of IP addressing for the interface and provide related parameters, as described here. (The IP Type section of the Add/Edit Interface dialog box for PIX 6.3 devices is described in Device Interface: IP Type (PIX 6.3).)
In multiple-context mode, interface IP addresses are set in the context configuration.
Note
Do not use addresses previously used for routers, hosts, or any other firewall device commands, such as an IP address in the global pool or a static NAT entry.
Also, do not specify IP Type information for an interface you intend to use as a redundant interface.
Step 1
In the Add/Edit Interface dialog box, choose a method for address assignment (Static IP, Use DHCP, or PPPoE (PIX and ASA 7.2+)) from the IP Type list, and then provide related parameters, as follows:
- Static IP – Provide a static IP Address and Subnet Mask that represents the security device on this interface’s connected network. The IP address must be unique for each interface.
The Subnet mask can be expressed in dotted decimal format (for example, 255.255.255.0), or by entering the number of bits in the network mask (for example, 24). Beginning from Version 4.13, Cisco Security Manager allows you to use 255.255.255.254 for point to point interface. Do not use 255.255.255.255 for an interface connected to the network because this will stop traffic on that interface. If you omit the Subnet Mask value, a “classful” network is assumed, as follows:
–
The Class A netmask (255.0.0.0) is assumed if the first octet of the IP Address is 1 through 126 (i.e., addresses 1.0.0.0 through 126.255.255.255).
–
The Class B netmask (255.255.0.0) is assumed if the first octet of the IP Address is 128 through 191 (i.e., addresses 128.0.0.0 through 191.255.255.255).
–
The Class C netmask (255.255.255.0) is assumed if the first octet of the IP Address is 192 through 223 (i.e., addresses 192.0.0.0 through 223.255.255.255).
Note Do not use addresses previously used for routers, hosts, or any other firewall device commands, such as an IP address in the global pool or a static NAT entry.
- Use DHCP – Enables Dynamic Host Configuration Protocol (DHCP) for automatic assignment of an IP address from a DHCP server on the connected network. The following options become available:
–
DHCP Learned Route Metric (required) – Assign an administrative distance to the learned route. Valid values are 1 to 255. The administrative distance for learned routes defaults to 1.
All routes have a value or “metric” that represents its priority of use. (This metric is also referred to as “administrative distance.”) When two or more routes to the same destination are available, devices use administrative distance to decide which route to use.
–
Obtain Default Route using DHCP – Select this option to obtain a default route from the DHCP server so that you do not need to configure a default static route. See also Configuring Static Routes.
–
Enable Tracking for DHCP Learned Route – If Obtain Default Route using DHCP is selected, you can select this option to enable route tracking via a specific Service Level Agreement (SLA) monitor. The following option becomes available:
–
Tracked SLA Monitor – Required if Enable Tracking for DHCP Learned Route is selected. Enter or Select the name of the SLA monitor object that defines the route tracking (connectivity monitoring) to be applied to this interface. See Monitoring Service Level Agreements (SLAs) To Maintain Connectivity for more information.
- PPPoE (PIX and ASA 7.2+) – Enables Point-to-Point Protocol over Ethernet (PPPoE) for automatic assignment of an IP address from a PPPoE server on the connected network; this option is not supported with failover. The following options become available:
–
VPDN Group Name (required) – Choose the Virtual Private Dialup Network (VPDN) group that contains the authentication method and user name/password to use for network connection, negotiation and authentication. See Managing VPDN Groups for more information.
–
IP Address – If provided, this static IP address is used for connection and authentication, instead of a negotiated address.
–
Subnet Mask – The subnet mask to be used in conjunction with the provided IP Address.
–
PPPoE Learned Route Metric (required) – Assign an administrative distance to the learned route. Valid values are 1 to 255; defaults to 1.
All routes have a value or “metric” that represents its priority of use. (This metric is also referred to as “administrative distance.”) When two or more routes to the same destination are available, devices use administrative distance to decide which route to use.
–
Obtain Default Route using PPPoE – Select this option to obtain a default route from the PPPoE server; sets the default routes when the PPPoE client has not yet established a connection. When using this option, you cannot have a statically defined route in the configuration.
–
Enable Tracking for PPPoE Learned Route – If Obtain Default Route using PPPoE is selected, you can select this option to enable route tracking for PPPoE-learned routes. The following options become available:
–
Dual ISP Interface – If you are defining interfaces for dual ISP support, choose Primary or Secondary to indicate which connection you are configuring.
–
Tracked SLA Monitor – Required if Enable Tracking for DHCP Learned Route is selected. Enter or Select the name of the SLA monitor object that defines the route tracking (connectivity monitoring) to be applied to this interface. See Monitoring Service Level Agreements (SLAs) To Maintain Connectivity for more information.
Note
You can configure DHCP and PPPoE only on the outside interface of a firewall device. If you have already configured PPPoE on the outside interface, it is no longer available as an option.
Step 2
Continue configuring the device interface in the Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
Device Interface: MAC Address
By default, a physical interface uses its “burned-in” MAC address, and all subinterfaces of a physical interface use the same burned-in MAC address.
A redundant interface uses the MAC address of the first physical interface that you add. If you change the order of the member interfaces in the configuration, then its MAC address changes to match the MAC address of the interface that is now listed first. If you manually assign a MAC address to the redundant interface, that is used regardless of the physical-interface MAC addresses.
Similarly, all interfaces assigned to an EtherChannel group share the same MAC address. By default, the EtherChannel uses the MAC address of the lowest-numbered member interface. However, you can manually configure a MAC address for the EtherChannel to prevent traffic disruption should the low-numbered interface be removed from the group.
You also might want to assign unique MAC addresses to subinterfaces. For example, your service provider might control access based on MAC addresses.
Further, if you use failover, you can provide a standby MAC address. If the active unit fails over and the standby unit becomes active, the new active unit starts using the active MAC addresses to minimize network disruption, while the old active unit uses the standby address.
Note
The following options appear only on the Advanced tab of the Add Interface and Edit Interface dialog boxes presented by PIX 7.2+ and ASA 7.2+ devices.
(Optional) To manually assign a private MAC address to the current interface:
Step 1
In the Add/Edit Interface dialog box, provide the desired MAC address in the Active MAC Address field.
MAC addresses are provided in H.H.H format, where H is a 16-bit hexadecimal digit. For example, the MAC address 00-0C-F1-42-4C-DE would be entered as 000C.F142.4CDE.
Note
In some cases, you may have to press the Tab key after entering the Active MAC Address to activate the Standby MAC Address field.
Step 2
If desired, provide a Standby MAC Address for use with device-level failover.
If the active unit fails over and the standby unit becomes active, the new active unit begins using the active MAC addresses to minimize network disruption, while the old active unit uses the standby address.
Step 3
Continue configuring the device interface in the Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM).
Configuring Hardware Ports on an ASA 5505
The Interfaces page displayed for ASA 5505 devices presents two tabbed panels: Hardware Ports and Interfaces. The table on the Hardware Ports panel displays currently configured switch ports for the selected ASA 5505.
Use the Configure Hardware Ports dialog box to configure the switch ports on an ASA 5505, including setting the mode, assigning a switch port to a VLAN, and setting the Protected option. (The following dialog-box parameter descriptions also describe the fields in the Hardware Ports table.)
Caution
The ASA 5505 does not support Spanning Tree Protocol for loop detection in the network. Therefore, you must ensure that any connection with the appliance does not end up in a network loop.
Navigation Path
You can access the Configure Hardware Ports dialog box by clicking Add Row or Edit Row on the Hardware Ports panel of the ASA 5505 Interfaces page. See Managing Device Interfaces, Hardware Ports, and Bridge Groups for more information.
Related Topics
Field Reference
Table 46-16 Configure Hardware Ports Dialog Box
|
|
Enable Interface |
Select this option to enable this switch port. You can deselect this option to disable the port, but retain its configuration information. |
Isolated |
Select this option to prevent this port from communicating with other isolated or “protected” switch ports on the same VLAN. You might want to prevent switch ports from communicating with each other if the devices on those ports are primarily accessed from other VLANs, if you do not need to allow intra-VLAN access, and you want to isolate the devices from each other in case of infection or other security breach. For example, if you have a DMZ that hosts three Web servers, you can isolate the Web servers from each other if you apply the Isolated option to each switch port. The inside and outside networks can both communicate with all three Web servers, and vice versa, but the Web servers cannot communicate with each other. |
Hardware Port |
Choose the switch port that you are configuring; all device ports are listed. |
Mode |
Choose a mode for this port:
- Access Port – Sets the port to access mode. Each access port can be assigned to one VLAN.
- Trunk Port – Sets the port to trunk mode using 802.1Q tagging. Trunk ports can carry multiple VLANs using 802.1Q tagging.
Trunk mode is available only with the Security Plus license. Trunk ports do not support untagged packets, there is no native VLAN support, and the appliance drops all packets that do not contain a tag. |
VLAN ID |
Enter VLAN ID(s) for this port, according to the chosen Mode:
- For Access Port mode, enter the ID of the VLAN to which this switch port is to be assigned.
- For Trunk Port mode, you can enter multiple VLAN IDs, and multiple ID ranges (such as 4-8), separated by commas.
Note For devices running operating system 7.2(2)18 or earlier, valid VLAN IDs are 1 to 1001; with version 7.2(2)19 or later, valid IDs are 1 to 4090. |
Duplex |
Choose a duplex option for the port: Full, Half, or Auto. The Auto setting is recommended, and the default. If you set Duplex to anything other than Auto for PoE ports Ethernet 0/6 or 0/7, then Cisco IP phones and Cisco wireless access points that do not support IEEE 802.3af will not be detected and supplied with power. |
Speed |
Choose a speed for the port: 10, 100, or Auto. The Auto setting is recommended, and the default. If you set Speed to anything other than Auto for PoE ports Ethernet 0/6 or 0/7, then Cisco IP phones and Cisco wireless access points that do not support IEEE 802.3af will not be detected and supplied with power. The default Auto setting also includes the Auto-MDI/MDIX feature. Auto-MDI/MDIX eliminates the need for crossover cabling by performing an internal crossover when a straight cable is detected during the auto-negotiation phase. Either Speed or Duplex must be set to Auto to enable Auto-MDI/MDIX for the interface. If you explicitly set both Speed and Duplex to a fixed value, thus disabling auto-negotiation for both settings, then Auto-MDI/MDIX is also disabled. |
Add/Edit Bridge Group Dialog Box
A transparent firewall connects the same network on its inside and outside interfaces, and supports only the two interfaces per context. However, you can increase the number of interfaces available to a context through use of bridge groups. You can configure up to eight bridge groups; on an FWSM each group can contain two interfaces; on an ASA 9.6.1 each group can contain 64 interfaces.
Each bridge group connects to a separate network. Bridge group traffic is isolated from other bridge groups; traffic is not routed to another bridge group within the security appliance—traffic must exit the security appliance to be routed by an external router back to another bridge group in the security appliance.
You might want to use more than one bridge group if you do not want the overhead of security contexts, or want to maximize your use of security contexts. Although the bridging functions are separate for each bridge group, many other functions are shared between all bridge groups. For example, all bridge groups share a syslog server or AAA server configuration. For complete security policy separation, use security contexts with one bridge group in each context.
Starting from Cisco Security Manager 4.13, the Bridge-group Virtual Interface (BVI) feature is extended to the routed firewall mode. Routed firewalls are implemented by means of configuring bridge-groups. A user can configure up to eight bridge groups and on an ASA 9.7.1 (Cisco Security Manager 4.13) each group can contain upto 64 interfaces. On versions prior to Cisco Security Manager 4.13, a user can configure a maximum of two bridge groups; with each group containing a maximum limit of four interfaces. In addition to the BVI features supported in the transparent mode, the routed firewall mode includes support for the following additional communication modes:
- Inter BVI communication
- BVI to Data Port communication (Layer 2 to Layer 3) and vice versa
For FWSM 3.1+ and ASA 8.4.1+ devices in transparent mode, the Interfaces page displays two tabbed panels: Interfaces and Bridge Groups. The following information applies to the Bridge Groups panel and the Add/Edit Bridge Group dialog box; refer to Add/Edit Interface Dialog Box (PIX 7.0+/ASA/FWSM) for information about the Interfaces panel.
Navigation Path
You can access the Add/Edit Bridge Group dialog box from the Bridge Groups panel of the Interfaces page.
Related Topics
Field Reference
Table 46-17 Add/Edit Bridge Group Dialog Box
|
|
|
Bridge Group |
Enter a name for this bridge group. |
Name |
Provide an identifier for this interface of up to 48 characters in length. The name should be a memorable name for the interface that relates to its use. However, if you are using failover, do not name interfaces that you are reserving for failover communications; this includes an EtherChannel intended for failover, as well as its member interfaces. Also, do not name interfaces intended for use as a member of a redundant-interface pair. Certain names are reserved for specific interfaces, in accordance with the interface naming conventions of the security appliance. As such, these reserved names enforce default, reserved security levels, as follows:
- Inside – Connects to your internal network. Must be the most secure interface.
- DMZ – “Demilitarized zone” attached to an intermediate interface. DMZ is also known as a perimeter network. You can name a DMZ interface any name you choose. Typically, DMZ interfaces are prefixed with “ DMZ ” to identify the interface type.
- Outside – Connects to an external network or the Internet. Must be the least secure interface.
Similarly, a subinterface name typically identifies its associated interface, in addition to its own unique identifier. For example, DMZoobmgmt could represent an out-of-band management network attached to the DMZ interface. Note Again, do not name the interface if you intend to use it for failover, or as a member of a redundant interface. See Chapter 50, “Configuring Failover” and Configuring Redundant Interfaces for more information. |
ID |
Enter an identifier for this bridge group; can be an integer between 1 and 100. |
Security Level |
Assign a security level to the VLAN interface. Valid values are from 0-100; 100 is the most secure. |
Available Interfaces |
Choose from a list of available interfaces or VLANs to assign to this bridge group; all available interfaces are listed. Note Starting from ASA 9.7.1(Cisco Security Manager 4.13), a maximum of 64 interfaces are supported per bridge group. |
Members in Group |
Displays the number of interfaces in the current bridge group |
IP Type |
Select the IP type for the interface.
- Static IP - Assign an IP address and subnet mask for the bridge-group interface.
- DHCP - Use DHCP to obtain an IP address for the interface.
– Obtain Default Route using DHCP - When selected, Cisco Security Manager uses the default route supplied by the DHCP server. |
IP Address |
Enter or Select a management IP address for the bridge group. A transparent firewall does not participate in IP routing. Thus, the only IP configuration required for a bridge group is this management IP address. This address is the source address for traffic originating on the security appliance, such as system messages or communications with AAA servers. You can also use this address for remote management access. Note IPv6 addresses are not supported for bridge groups. |
Netmask |
Network mask for the specified IP address. You can express the value in dotted decimal format (for example, 255.255.255.0) or by entering the number of bits in the network mask (for example, 24). Note Do not use 255.255.255.255 for an interface connected to the network because this will stop traffic on that interface. |
Description |
You can enter an optional description for this bridge group. |
|
Enable IPv6 |
Check this box to enable IPv6 and configure IPv6 addresses on this bridge group. You can deselect this option to disable IPv6 on the bridge group, but retain the configuration information. |
Enforce EUI-64 |
When selected, use of Modified EUI-64 format interface identifiers in IPv6 addresses on a local link is enforced. When this option is enabled on a bridge group, the source addresses of IPv6 packets received on the bridge group interface are verified against the source MAC addresses to ensure that the interface identifiers use the Modified EUI-64 format. If the interface identifier in an IPv6 packet is not in the Modified EUI-64 format, the packet is dropped and the following system log message is generated: %PIX|ASA-3-325003: EUI-64 source address check failed. Address format verification is performed only when a flow is created. Packets from an existing flow are not checked. Additionally, address verification can be performed only for hosts on the local link. Packets received from hosts behind a router will fail the address format verification, and be dropped, because their source MAC address will be the router MAC address and not the host MAC address. The Modified EUI-64 format interface identifier is derived from the 48-bit link-layer (MAC) address by inserting the hex number FFFE between the upper three bytes (OUI field) and the lower 3 bytes (serial number) of the link-layer address. To ensure the chosen address is from a unique Ethernet MAC address, the next-to-lowest order bit in the high-order byte is inverted (universal/local bit) to indicate the uniqueness of the 48-bit address. For example, an interface with a MAC address of 00E0.B601.3B7A would have a 64-bit interface ID of 02E0:B6FF:FE01:3B7A. |
DAD Attempts |
To specify the number of consecutive neighbor solicitation messages that are sent on a bridge group interface during duplicate address detection (DAD), enter a number from 0 to 600 in this field. Entering 0 disables duplicate address detection on the interface. Entering 1 configures a single transmission without follow-up transmissions; this is the default. Duplicate address detection verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection uses neighbor solicitation messages to verify the uniqueness of unicast IPv6 addresses. When duplicate address detection identifies a duplicate address, the state of the address is set to DUPLICATE and the address is not used. If the duplicate address is the link-local address of the interface, the processing of IPv6 packets is disabled on the interface and an error message similar to the following is issued: %PIX-4-DUPLICATE: Duplicate address FE80::1 on outside If the duplicate address is a global address of the interface, the address is not used and an error message is issued, similar to that shown previously for a duplicate link-local address. All configuration commands associated with the duplicate address remain as-configured while the state of the address is set to DUPLICATE. If the link-local address for an interface changes, duplicate address detection is performed on the new link-local address, and all other IPv6 address associated with the interface are regenerated (that is, duplicate address detection is performed only on the new link-local address). |
NS Interval |
The interval between IPv6 neighbor solicitation retransmissions, in milliseconds. Valid values range from 1000 to 3600000 milliseconds; the default value is 1000 milliseconds. Note This value is included in all IPv6 router advertisements sent out on this interface. |
Reachable Time |
The amount of time, in milliseconds, within which a remote IPv6 node is considered still reachable, after initial reachability was confirmed. Valid values range from 0 to 3600000 milliseconds, the default value is 0. When 0 is used for the value, the reachable time is set as undetermined—it is up to the receiving devices to set and track reachable time. A configured time enables detection of unavailable neighbors. A shorter time allows detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation. |
Managed Config Flag |
Whether or not to set the flag "managed-config-flag" in the IPv6 router advertisement packet. |
Other Config Flag |
Whether or not to set the flag "other-config-flag" in the IPv6 router advertisement packet. |
Enable RA |
When checked, IPv6 router advertisement transmissions are enabled on the interface. The following options are enabled:
- RA Lifetime – The “router lifetime” value specifies how long nodes on the local link should consider the security appliance as the default router on the link. Valid values range from 0 to 9000 seconds; the default is 1800 seconds. Entering 0 indicates that the security appliance should not be considered a default router on the selected interface.
Any non-zero value should not be less than the following RA Interval value. Note This value is included in all IPv6 router advertisements sent out on this interface.
- RA Interval – The interval between IPv6 router advertisement transmissions on this interface. Valid values range from 3 to 1800 seconds, (or from 500 to 1800000 milliseconds if the following RA Interval in Milliseconds option is checked); the default is 200 seconds.
The interval between transmissions should be less than or equal to the RA Lifetime value if it is non-zero. To prevent synchronization with other IPv6 nodes, randomly adjust the actual value used to within 20 percent of the desired value.
- RA Interval in Milliseconds – Checking this option indicates that the provided RA Interval value is in milliseconds, rather than seconds.
|
Interface IPv6 Addresses |
The IPv6 addresses assigned to the bridge group interface are specified in this section of the dialog box.
- Link-Local Address – To override the link-local address that is automatically generated for the interface, enter the desired IPv6 link-local address in this field.
The link-local address is composed of the link-local prefix FE80::/64 and the interface ID in Modified EUI-64 format. For example, an interface with a MAC address of 00E0.B601.3B7A would have a link-local address of FE80::2E0:B6FF:FE01:3B7A. An error will occur if another host is using the specified address.
- Enable Address Auto-Configuration – Select this option to enable automatic configuration of IPv6 addresses on the interface using stateless autoconfiguration. The addresses are configured based on the prefixes received in Router Advertisement (RA) messages. If a link-local address has not been configured, then one is automatically generated for this interface. An error occurs if another host is already using the generated link-local address.
– Trust the DHCP Servers for default gateway – Select this radio button to install a default route from Router Advertisements that come from a trusted source - the directly-connected network. – Ignore trust and accept router advertisements – Select this radio button to install a default route from Router Advertisements that come from another network.
- The table in this section displays the IPv6 addresses assigned to this interface. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.)
Add Row and Edit Row open the IPv6 Address for Interface Dialog Box. |
Interface IPv6 Prefixes |
Use the table in this section to configure which IPv6 prefixes (that is, the network portion of the IPv6 addresses) are included in IPv6 router advertisements. Use the Add Row, Edit Row, and Delete Row buttons below this table to manage these entries. (These are standard buttons, as described in Using Tables.) Add Row and Edit Row open the IPv6 Prefix Editor Dialog Box. |
Advanced Interface Settings (PIX/ASA/FWSM)
Advanced configuration options are available for interfaces on FWSMs and ASA/PIX 7.0+ devices operating in single-context mode and for ASA 9.0+ devices operating in single-context mode or multi-context mode.
These are general device-related settings; that is, they are not applied to individual interfaces.
Note
The information in this section does not apply to PIX 6.3 devices, nor to security devices in multiple-context mode.
The Advanced Interface Settings dialog box includes the following elements:
- MAC Address Auto - Enable this option to automatically assign private MAC addresses to each shared context interface. You can also, optionally, set a user-defined prefix as part of the MAC address. The prefix is a decimal value between 0 and 65535. If you do not enter a prefix, then the ASA generates a default prefix. This prefix is converted to a 4-digit hexadecimal number. The prefix ensures that each ASA uses unique MAC addresses (using different prefix values), so you can have multiple ASAs on a network segment, for example,
- Traffic between interfaces with same security levels – This parameter controls communication between interfaces and subinterfaces on the same security level. If you enable same security interface communication, you can still configure interfaces at different security levels as usual. Refer to Enabling Traffic between Interfaces with the Same Security Level for more information.
- PPPoE Users button – Click this button to open the PPPoE Users dialog box, where you can add, edit and delete PPPoE users, as described in Managing the PPPoE Users List. This option is available only for ASA and PIX 7.0+ devices.
- VPDN Groups (PIX and ASA 7.2+) – This table lists currently defined VPDN Groups. The buttons below the table are used to add, edit and delete VPDN group entries, as described in Managing VPDN Groups.
- LACP System Priority (ASA 8.4.1+) – All systems participating in EtherChannel link aggregation require a Link Aggregation Control Protocol (LACP) System Priority. The value can be 1 to 65535, with the higher number signifying lower priority. The default is 32768.
This value is combined with the system MAC address to form the system’s LACP identifier, and thus is applicable only for EtherChannel interfaces. See Configuring EtherChannels, for more information.
Note
Additional LACP parameters are available in the Edit Interface dialog box for individual interfaces assigned to an EtherChannel; see Editing LACP Parameters for an Interface Assigned to an EtherChannel, for more information.
Note
LACP System Priority is not supported in Cisco Firepower 9000 devices.
- Static Port Priority (ASA 9.2.1+ Cluster in Spanned mode) – Disables dynamic port priority in LACP. Some switches do not support dynamic port priority, so this parameter improves switch compatibility. Enabling static port priority enables support of 16 active spanned EtherChannel members. Without this parameter, only 8 active members and 8 standby members are supported. If you enable this parameter, then you cannot use any standby members; all members are active. This parameter is not part of the bootstrap configuration, and is replicated from the control unit to the data units.
Note
If you enable Static Port Priority, 16 nodes can be part of a cluster instead of 8 nodes.
- Director-Localization – In Geo clustering where, multiple Data Center sites are supported, the inter-cluster round-trip time (RTT) latency is higher than intra-DC. This delay impacts the performance of applications like the VoIP media stream. Beginning with 4.13, the director localization is used to minimize the RTT latency and the delays in performance lookup messages. Enabling this option makes the flow owner and director to be in the same DC site, so that the flow owner lookup is done in local DC site, and the traffic is contended within the same site.
Navigation Path
You can open the Advanced Interface Settings dialog box by clicking the Advanced button at the bottom of the Interfaces page (for non-5505 ASAs, PIX 7.0+ devices, and FWSMs), or at the bottom of the Interfaces tab on the ASA 5505 Ports and Interfaces page.
Related Topics
Enabling Traffic between Interfaces with the Same Security Level
The Advanced Interface Settings (PIX/ASA/FWSM) dialog box presented for a single-context security device includes the “Traffic between interfaces with the same security level” drop-down list, as described in this section.
By default, interfaces or subinterfaces on the same security level cannot communicate with each other. Allowing communication between same-security interfaces provides the following benefits:
- You can configure more than 101 communicating interfaces.
If you use different levels for each interface and do not assign any interfaces to the same security level, you can configure only one interface per level (0 to 100).
- You can allow traffic to flow freely between all same-security interfaces without access lists.
Note
If you enable NAT control, you do not need to configure NAT between same-security-level interfaces.
Step 1
In the Advanced Interface Settings dialog box, choose the option that identifies how you want this device to handle Traffic between interfaces with the same security levels :
- Disabled —Communication between interfaces on the same security level is not allowed.
- Inter-interface —Enables traffic flows between interfaces with the same security level setting. When this option is enabled, you are not required to define translation rules to enable traffic flow between interfaces in the firewall device.
- Intra-interface —Enables traffic flows between subinterfaces with the same security level setting. When this option is enabled, you are not required to define translation rules to enable traffic flow between subinterfaces assigned to an interface.
- Both —Allows both intra- and inter-interface communications among interfaces and subinterfaces with the same security level.
Step 2
Continue with Advanced Interface Settings (PIX/ASA/FWSM) configuration, or click OK to close the Advanced Interface Settings dialog box.
Managing the PPPoE Users List
Point-to-Point Protocol over Ethernet (PPPoE) allows standard PPP communication between a security device and an external ISP, via an Ethernet interface on the device. To establish a communication link, the device must provide authentication credentials and obtain network parameters. This is accomplished using a Virtual Private Dialup Network (VPDN) group, which basically consists of established PPPoE user credentials (i.e., a user name and password) and an authentication protocol. See Managing VPDN Groups for more information about VPDN groups.
The PPPoE user credentials available for use with VPDN groups are maintained in the PPPoE Users dialog box, which you can access from the Advanced Interface Settings (PIX/ASA/FWSM) dialog box, and from the Add/Edit VPND Group dialog boxes.
Adding and Editing PPPoE Users
The PPPoE Users dialog box presents a table of currently defined PPPoE users, along with standard Add Row, Edit Row, and Delete Row buttons. The Add Row button opens the Add PPPoE User dialog box; the Edit Row button opens the virtually identical Edit PPPoE User dialog box.
Enter or edit the following PPPoE user parameters, and then click OK to close the Add (Edit) PPPoE User dialog box and return to the Advanced Interface Settings dialog box.
Note
PPPoE user options are not available on Firewall Service Modules (FWSMs).
Field Reference
Table 46-18 Add and Edit PPPoE User Dialog Boxes
|
|
Username |
The name assigned to this user account; generally provided by the external ISP. |
Password |
The password assigned to this user account; also generally provided by the external ISP. |
Confirm |
Re-enter the password. |
Store Username and Password in Local Flash |
If checked, this PPPoE user information will be stored in the device’s local flash memory, ensuring it cannot be inadvertently overwritten. |
Managing VPDN Groups
A Virtual Private Dialup Network (VPDN) group—basically an established PPPoE user and an authentication protocol—is used by a security device to contact an external ISP and authenticate itself, in order to establish a PPPoE communications link and obtain network parameters. (See Managing the PPPoE Users List for information about establishing PPPoE users.)
Available VPDN groups are maintained in the Advanced Interface Settings dialog box, which opens when you click the Advanced button at the bottom of the Interfaces page, as described in Advanced Interface Settings (PIX/ASA/FWSM).
Adding and Editing VPND Groups
The Advanced Interface Settings dialog box includes a table of currently defined VPDN groups, and standard Add Row, Edit Row, and Delete Row buttons. The Add Row button opens the Add VPDN Group dialog box; the Edit Row button opens the virtually identical Edit VPDN Group dialog box.
Enter or edit the following VPDN group parameters, and then click OK to close the Add (Edit) VPDN Group dialog box and return to the Advanced Interface Settings dialog box.
Note
VPDN group options are not available on Firewall Service Modules (FWSMs).
Field Reference
Table 46-19 Add and Edit VPND Group Dialog Boxes
|
|
Group Name |
A name to identify this group in Security Manager; up to 63 characters. |
PPPoE Username |
The name identifying the PPPoE credentials to be used by this group for authentication with an ISP; choose from the list of available PPPoE users. Choose Edit User from this list to open the PPPoE Users dialog box, where you can add or edit a user for this option. Refer to Managing the PPPoE Users List for information about creating and editing users. |
PPP Authentication |
Select the PPP Authentication method:
- PAP – Password Authentication Protocol, with exchange of credentials in clear text.
- CHAP – Challenge Handshake Authentication Protocol, with encrypted credential exchange.
- MSCHAP – Microsoft’s CHAP, version 1 only.
|