ASDM Book 1: Cisco ASA Series General Operations ASDM Configuration Guide, 7.2

OSPF Support for Fast Hello Packets

The OSPF Support for Fast Hello Packets feature provides a way to configure the sending of hello packets in intervals less than 1 second. Such a configuration would result in faster convergence in an Open Shortest Path First (OSPF) network.

Prerequisites for OSPF Support for Fast Hello Packets

OSPF must be configured in the network already or configured at the same time as the OSPF Support for Fast Hello Packets feature.

Information About OSPF Support for Fast Hello Packets

The following sections describe concepts related to OSPF support for fast hello packets:

• OSPF Hello Interval and Dead Interval
• OSPF Fast Hello Packets
• Benefits of OSPF Fast Hello Packets

OSPF Hello Interval and Dead Interval

OSPF hello packets are packets that an OSPF process sends to its OSPF neighbors to maintain connectivity with those neighbors. The hello packets are sent at a configurable interval (in seconds). The defaults are 10 seconds for an Ethernet link and 30 seconds for a non broadcast link. Hello packets include a list of all neighbors for which a hello packet has been received within the dead interval. The dead interval is also a configurable interval (in seconds), and defaults to four times the value of the hello interval. The value of all hello intervals must be the same within a network. Likewise, the value of all dead intervals must be the same within a network.

These two intervals work together to maintain connectivity by indicating that the link is operational. If a router does not receive a hello packet from a neighbor within the dead interval, it will declare that neighbor to be down.

OSPF Fast Hello Packets

OSPF fast hello packets refer to hello packets being sent at intervals of less than 1 second. To understand fast hello packets, you should already understand the relationship between OSPF hello packets and the dead interval. See the section OSPF Hello Interval and Dead Interval .

OSPF fast hello packets are achieved by using the ospf dead-interval command. The dead interval is set to 1 second, and the hello-multiplier value is set to the number of hello packets you want sent during that 1 second, thus providing subsecond or "fast" hello packets.

When fast hello packets are configured on the interface, the hello interval advertised in the hello packets that are sent out this interface is set to 0. The hello interval in the hello packets received over this interface is ignored.

The dead interval must be consistent on a segment, whether it is set to 1 second (for fast hello packets) or set to any other value. The hello multiplier need not be the same for the entire segment as long as at least one hello packet is sent within the dead interval.

Benefits of OSPF Fast Hello Packets

The benefit of the OSPF Fast Hello Packets feature is that your OSPF network will experience faster convergence time than it would without fast hello packets. This feature allows you to detect lost neighbors within 1 second. It is especially useful in LAN segments, where neighbor loss might not be detected by the Open System Interconnection (OSI) physical layer and data-link layer.

Implementation Differences Between OSPFv2 and OSPFv3

OSPFv3 is not backward compatible with OSPFv2. To use OSPF to route both IPv4 and IPv6 traffic, you must run both OSPFv2 and OSPFv3 at the same time. They coexist with each other, but do not interact with each other.

The additional features that OSPFv3 provides include the following:

• Protocol processing per link.
• Removal of addressing semantics.
• Addition of flooding scope.
• Support for multiple instances per link.
• Use of the IPv6 link-local address for neighbor discovery and other features.
• LSAs expressed as prefix and prefix length.
• Addition of two LSA types.
• Handling of unknown LSA types.
• Authentication support using the IPsec ESP standard for OSPFv3 routing protocol traffic, as specified by RFC-4552.

Using Clustering

For more information about dynamic routing and clustering, see Dynamic Routing and Clustering.

For more information about using clustering, see Chapter9, “ASA Cluster”

Redistributing Routes Into OSPFv2

The ASA can control the redistribution of routes between OSPFv2 routing processes.

Note If you want to redistribute a route by defining which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process, you must first generate a default route. See Configuring Static and Default Routes, and then define a route map according to the Defining a Route Map.

To redistribute static, connected, RIP, or OSPFv2 routes into an OSPFv2 process, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Redistribution.

The Redistribution pane displays the rules for redistributing routes from one routing process into an OSPF routing process. You can redistribute routes discovered by RIP and OSPF into the EIGRP routing process. You can also redistribute static and connected routes into the EIGRP routing process. You do not need to redistribute static or connected routes if they fall within the range of a network that has been configured through the Setup > Networks tab.

Step 2 Click Add or Edit.

Alternatively, double-clicking a table entry in the Redistribution pane (if any) opens the Add/Edit OSPF Redistribution Entry dialog box for the selected entry.

Note All steps that follow are optional.

The Add/Edit OSPF Redistribution Entry dialog box lets you add a new redistribution rule or edit an existing redistribution rule in the Redistribution table. Some of the redistribution rule information cannot be changed when you are editing an existing redistribution rule.

Step 3 Choose the OSPF process associated with the route redistribution entry. If you are editing an existing redistribution rule, you cannot change this setting.

Step 4 Choose the source protocol from which the routes are being redistributed. You can choose one of the following options:

• Static—Redistributes static routes to the OSPF routing process.
• Connected—Redistributes connected routes (routes established automatically by virtue of having IP address enabled on the interface) to the OSPF routing process. Connected routes are redistributed as external to the AS.
• OSPF—Redistributes routes from another OSPF routing process. Choose the OSPF process ID from the list. If you choose this protocol, the Match options on this dialog box become visible. These options are not available when redistributing static, connected, RIP, or EIGRP routes. Skip to Step 5.
• RIP—Redistributes routes from the RIP routing process.
• BGP— Redistribute routes from the BGP routing process.
• EIGRP—Redistributes routes from the EIGRP routing process. Choose the autonomous system number of the EIGRP routing process from the list.

Step 5 If you have chosen OSPF for the source protocol, choose the conditions used for redistributing routes from another OSPF routing process into the selected OSPF routing process. These options are not available when redistributing static, connected, RIP, or EIGRP routes. The routes must match the selected condition to be redistributed. You can choose one or more of the following match conditions:

• Internal—The route is internal to a specific AS.
• External 1—Routes that are external to the autonomous system, but are imported into OSPF as Type 1 external routes.
• External 2—Routes that are external to the autonomous system, but are imported into OSPF as Type 2 external routes.
• NSSA External 1—Routes that are external to the autonomous system, but are imported into OSPF as Type 2 NSSA routes.
• NSSA External 2—Routes that are external to the autonomous system, but are imported into OSPF as Type 2 NSSA routes.

Step 6 In the Metric Value field, enter the metric value for the routes being redistributed. Valid values range from 1 to 16777214.

When redistributing from one OSPF process to another OSPF process on the same device, the metric will be carried through from one process to the other if no metric value is specified. When redistributing other processes to an OSPF process, the default metric is 20 when no metric value is specified.

Step 7 Choose one of the following options for the Metric Type.

• If the metric is a Type 1 external route, choose 1.
• If the metric is a Type 2 external route, choose 2.

Step 8 Enter the tag value in the Tag Value field.

The tag value is a 32-bit decimal value attached to each external route that is not used by OSPF itself, but may be used to communicate information between ASBRs. Valid values range from 0 to 4294967295.

Step 9 Check the Use Subnets check box to enable the redistribution of subnetted routes. Uncheck this check box to cause only routes that are not subnetted to be redistributed.

Step 10 Choose the name of the route map to apply to the redistribution entry from the Route Map drop-down list.

Step 11 If you need to add or configure a route map, click Manage.

The Configure Route Map dialog box appears.

Step 12 Click Add or Edit to define which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process. For more information, see Defining a Route Map.

Step 13 Click OK.

Configuring Route Summarization When Redistributing Routes Into OSPFv2

When routes from other protocols are redistributed into OSPF, each route is advertised individually in an external LSA. However, you can configure the ASA to advertise a single route for all the redistributed routes that are included for a specified network address and mask. This configuration decreases the size of the OSPF link-state database.

Routes that match the specified IP address mask pair can be suppressed. The tag value can be used as a match value for controlling redistribution through route maps.

There are two areas that you can configure for route summarization:

• Adding a Route Summary Address
• Adding or Editing an OSPF Summary Address

Adding a Route Summary Address

The Summary Address pane displays information about the summary addresses configured for each OSPF routing process.

Routes learned from other routing protocols can be summarized. The metric used to advertise the summary is the smallest metric of all the more specific routes. Summary routes help reduce the size of the routing table.

Using summary routes for OSPF causes an OSPF ASBR to advertise one external route as an aggregate for all redistributed routes that are covered by the address. Only routes from other routing protocols that are being redistributed into OSPF can be summarized.

Note OSPF does not support summary-address 0.0.0.0 0.0.0.0.

To configure the software advertisement on one summary route for all redistributed routes included for a network address and mask, perform the following steps:

Step 1 In the main ASDM home page, choose Configuration > Device Setup > Routing > OSPF > Summary Address.

Step 2 Click Add.

The Add OSPF Summary Address Entry dialog box appears. You can add new entries to existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

Step 3 Choose the specified OSPF Process ID associated with the summary address from the OSPF Process drop-down list. You cannot change this information when editing an existing entry.

Step 4 Enter the IP address of the summary address in the IP Address field. You cannot change this information when editing an existing entry.

Step 5 Choose the network mask for the summary address from the Netmask drop-down list. You cannot change this information when editing an existing entry.

Step 6 Check the Advertise check box to advertise the summary route. Uncheck this check box to suppress routes that fall under the summary address. By default, this check box is checked.

The Tag value displays a 32-bit decimal value that is attached to each external route. This value is not used by OSPF itself, but may be used to communicate information between ASBRs.

Step 7 Click OK.

Adding or Editing an OSPF Summary Address

To add or edit OSPF summary address setting, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Route Summarization tab.

The Add/Edit a Route Summarization Entry dialog box appears.

The Add/Edit a Route Summarization Entry dialog box allows you to add new entries to or modify existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

Step 3 Choose the specified OSPF Process ID associated with the summary address from the OSPF Process drop-down list. You cannot change this information when editing an existing entry.

Step 4 Enter the IP address of the summary address in the IP Address field. You cannot change this information when editing an existing entry.

Step 5 Enter the network mask for the summary address from the Netmask drop-down list. You cannot change this information when editing an existing entry.

Step 6 Check the Advertise check box to advertise the summary route. Uncheck this check box to suppress routes that fall under the summary address. By default, this check box is checked.

Configuring Route Summarization Between OSPFv2 Areas

Route summarization is the consolidation of advertised addresses. This feature causes a single summary route to be advertised to other areas by an area boundary router. In OSPF, an area boundary router advertises networks in one area into another area. If the network numbers in an area are assigned in a way so that they are contiguous, you can configure the area boundary router to advertise a summary route that includes all the individual networks within the area that fall into the specified range.

To define an address range for route summarization, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Route Summarization tab.

The Add/Edit a Route Summarization Entry dialog box appears.

The Add/Edit a Route Summarization Entry dialog box allows you to add new entries to or modify existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

Step 3 Enter the OSPF Area ID in the Area ID field. You cannot change this information when editing an existing entry.

Step 4 Enter the IP address of the summary address in the IP Address field. You cannot change this information when editing an existing entry.

Configuring OSPFv2 Interface Parameters

You can change some interface-specific OSPFv2 parameters, if necessary. You are not required to change any of these parameters, but the following interface parameters must be consistent across all routers in an attached network: the Hello interval, the Dead interval, and the Authentication key. If you configure any of these parameters, be sure that the configurations for all routers on your network have compatible values.

To configure OSPFv2 interface parameters, perform the following steps:

In ASDM, the Interface pane lets you configure interface-specific OSPF routing properties, such as OSPF message authentication and properties. There are two tabs that help you configure interfaces in OSPF:

• The Authentication tab displays the OSPF authentication information for the ASA interfaces.
• The Properties tab displays the OSPF properties defined for each interface in a table format.

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Interface.

Step 2 Click the Authentication tab to display the authentication information for the ASA interfaces. Double-clicking a row in the table opens the Edit OSPF Authentication Interface dialog box for the selected interface.

Step 3 Click Edit.

The Edit OSPF Authentication Interface dialog box appears. The Edit OSPF Interface Authentication dialog box lets you configure the OSPF authentication type and parameters for the selected interface.

Step 4 Choose the Authentication type from the Authentication drop-down list according to the following options:

• None to disable OSPF authentication.
• Authentication Password to use clear text password authentication (not recommended where security is a concern).
• MD5 to use MD5 authentication (recommended).
• Area (Default) to use the authentication type specified for the area. See Configuring OSPFv2 Area Parameters for information about configuring area authentication. Area authentication is disabled by default. Therefore, unless you have previously specified an area authentication type, interfaces set to area authentication have authentication disabled until you configure this setting.

Step 5 Click the radio button in the Authentication Password area, which includes the settings for entering the password when password authentication is enabled.

a. In the Enter Password field, type a text string of up to eight characters.

b. In the Re-enter Password field, retype the password.

Step 6 Choose the settings for MD5 IDs and keys in the ID area, which includes the settings for entering the MD5 keys and parameters when MD5 authentication is enabled. All devices on the interface using OSPF authentication must use the same MD5 key and ID.

a. In the Key ID field, enter a numerical key identifier. Valid values range from 1 to 255. The Key ID displays for the selected interface.

b. In the Key field, enter an alphanumeric character string of up to 16 bytes. The key displays for the selected interface.

c. Click Add or Delete to add or delete the specified MD5 key to the MD5 ID and Key table.

Step 7 Click OK.

Step 8 Click the Properties tab.

Step 9 Choose the interface that you want to edit. Double-clicking a row in the table opens the Properties tab dialog box for the selected interface.

Step 10 Click Edit.

The Edit OSPF Interface Properties dialog box appears. The Interface field displays the name of the interface for which you are configuring OSPF properties. You cannot edit this field.

Step 11 Check or uncheck the Broadcast check box to specify that the interface is a broadcast interface.

By default, this check box is checked for Ethernet interfaces. Uncheck this check box to designate the interface as a point-to-point, nonbroadcast interface. Specifying an interface as point-to-point, nonbroadcast lets you transmit OSPF routes over VPN tunnels.

When an interface is configured as point-to-point, non-broadcast, the following restrictions apply:

• You can define only one neighbor for the interface.
• You need to manually configure the neighbor. See Defining Static OSPFv2 Neighbors for more information.
• You need to define a static route pointing to the crypto endpoint. See Configuring Static and Default Routes for more information.
• If OSPF over a tunnel is running on the interface, regular OSPF with an upstream router cannot be run on the same interface.
• You should bind the crypto map to the interface before specifying the OSPF neighbor to ensure that the OSPF updates are passed through the VPN tunnel. If you bind the crypto map to the interface after specifying the OSPF neighbor, use the clear local-host all command to clear OSPF connections so that the OSPF adjacencies can be established over the VPN tunnel.

Step 12 Configure the following options:

• Enter a value in the Cost field, which determines the cost of sending a packet through the interface. The default value is 10.
• In the Priority field, enter the OSPF router priority value.

When two routers connect to a network, both attempt to become the designated router. The device with the higher router priority becomes the designated router. If there is a tie, the router with the higher router ID becomes the designated router.

Valid values for this setting range from 0 to 255. The default value is 1. Entering 0 for this setting makes the router ineligible to become the designated router or backup designated router. This setting does not apply to interfaces that are configured as point-to-point, nonbroadcast interfaces.

• Check or uncheck the MTU Ignore check box.

OSPF checks whether neighbors are using the same MTU on a common interface. This check is performed when neighbors exchange DBD packets. If the receiving MTU in the DBD packet is higher than the IP MTU configured on the incoming interface, OSPF adjacency will not be established.

• Check or uncheck the Database filter check box.

Use this setting to filter the outgoing LSA interface during synchronization and flooding. By default, OSPF floods new LSAs over all interfaces in the same area, except the interface on which the LSA arrives. In a fully meshed topology, this flooding can waste bandwidth and lead to excessive link and CPU usage. Checking this check box prevents OSPF flooding of the LSA on the selected interface.

Step 13 (Optional) Click Advanced to display the Edit OSPF Advanced Interface Properties dialog box, which lets you change the values for the OSPF hello interval, retransmit interval, transmit delay, and dead interval.

Typically, you only need to change these values from the defaults if you are experiencing OSPF problems on your network.

Step 14 In the Intervals section, enter values for the following:

• The Hello Interval, which specifies the interval, in seconds, between hello packets sent on an interface. The smaller the hello interval, the faster topological changes are detected, but more traffic is sent on the interface. This value must be the same for all routers and access servers on a specific interface. Valid values range from 1 to 8192 seconds. The default value is 10 seconds.
• The Retransmit Interval, which specifies the time, in seconds, between LSA retransmissions for adjacencies belonging to the interface. When a router sends an LSA to its neighbor, it keeps the LSA until it receives the acknowledgement message. If the router receives no acknowledgement, it will resend the LSA. Be conservative when setting this value, or needless retransmission can result. The value should be larger for serial lines and virtual links. Valid values range from 1 to 8192 seconds. The default value is 5 seconds.
• The Transmit Delay, which specifies the estimated time, in seconds, required to send an LSA packet on the interface. LSAs in the update packet have their ages increased by the amount specified by this field before transmission. If the delay is not added before transmission over a link, the time in which the LSA propagates over the link is not considered. The value assigned should take into account the transmission and propagation delays for the interface. This setting has more significance on very low-speed links. Valid values range from 1 to 8192 seconds. The default value is 1 second.

Step 15 In the Detecting Lost Neighbors section, do one of the following:

• Click Configure interval within which hello packets are not received before the router declares the neighbor to be down. In the Dead Interval field, specify the interval, in seconds, in which no hello packets are received, causing neighbors to declare a router down. Valid values range from 1 to 8192 seconds. The default value of this setting is four times the interval that was set in the Hello Interval field.
• Click Send fast hello packets within 1 seconds dead interval. In the Hello multiplier field, specify the number of hello packets to be sent per second. Valid values are between 3 and 20.

Configuring OSPFv2 Area Parameters

You can configure several OSPF area parameters. These area parameters (shown in the following task list) include setting authentication, defining stub areas, and assigning specific costs to the default summary route. Authentication provides password-based protection against unauthorized access to an area.

Stub areas are areas into which information on external routes is not sent. Instead, there is a default external route generated by the ABR into the stub area for destinations outside the autonomous system. To take advantage of the OSPF stub area support, default routing must be used in the stub area.

To specify OSPFv2 area parameters for your network, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Area/Networks tab.

The Add OSPF Area dialog box appears.

Step 3 Choose one of the following Area Type options:

• Normal to make the area a standard OSPF area. This option is selected by default when you first create an area.
• Stub to make the area a stub area. Stub areas do not have any routers or areas beyond it. Stub areas prevent AS External LSAs (Type 5 LSAs) from being flooded into the stub area. When you create a stub area, you have the option of preventing summary LSAs (Types 3 and 4) from being flooded into the area by unchecking the Summary check box.
• Summary to prevent LSAs from being sent into the stub area when the area being defined is a stub area, uncheck this check box. By default, this check box is checked for stub areas.
• NSSA to make the area a not-so-stubby area. NSSAs accept Type 7 LSAs. When you create the NSSA, you have the option of preventing summary LSAs from being flooded into the area by unchecking the Summary check box. You can also disable route redistribution by unchecking the Redistribute check box and checking the Default Information Originate check box.

Step 4 Enter the IP address in the IP Address field of the network or host to be added to the area. Use 0.0.0.0 with a netmask of 0.0.0.0 to create the default area. You can only enter 0.0.0.0 in one area.

Step 5 Enter the network mask in the Network Mask field for the IP address or host to be added to the area. If adding a host, choose the 255.255.255.255 mask.

Step 6 Choose the OSPF Authentication type from the following options:

• None to disable OSPF area authentication. This is the default setting.
• Password to provide a clears text password for area authentication, which is not recommended where security is a concern.
• MD5 to allow MD5 authentication.

Step 7 Enter a value in the Default Cost field to specify a default cost for the OSPF area.

Valid values range from 0 to 65535. The default value is 1.

Step 8 Click OK.

Configuring an OSPFv2 NSSA

The OSPFv2 implementation of an NSSA is similar to an OSPFv2 stub area. NSSA does not flood Type 5 external LSAs from the core into the area, but it can import autonomous system external routes in a limited way within the area.

NSSA imports Type 7 autonomous system external routes within an NSSA area by redistribution. These Type 7 LSAs are translated into Type 5 LSAs by NSSA ABRs, which are flooded throughout the whole routing domain. Summarization and filtering are supported during the translation.

You can simplify administration if you are an ISP or a network administrator that must connect a central site using OSPFv2 to a remote site that is using a different routing protocol with NSSA.

Before the implementation of NSSA, the connection between the corporate site border router and the remote router could not be run as an OSPFv2 stub area because routes for the remote site could not be redistributed into the stub area, and two routing protocols needed to be maintained. A simple protocol such as RIP was usually run and handled the redistribution. With NSSA, you can extend OSPFv2 to cover the remote connection by defining the area between the corporate router and the remote router as an NSSA.

Before you use this feature, consider these guidelines:

• You can set a Type 7 default route that can be used to reach external destinations. When configured, the router generates a Type 7 default into the NSSA or the NSSA area boundary router.
• Every router within the same area must agree that the area is NSSA; otherwise, the routers cannot communicate with each other.

To specify area parameters for your network to configure an OSPFv2 NSSA, perform the following steps:

Step 1 From the main ASDM home page, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Area/Networks tab.

Step 3 Click Add.

The Add OSPF Area dialog box appears.

Step 4 Click the NSSA radio button in the Area Type area.

Choose this option to make the area a not-so-stubby area. NSSAs accept Type 7 LSAs. When you create the NSSA, you have the option of preventing summary LSAs from being flooded into the area by unchecking the Summary check box. You can also disable route redistribution by unchecking the Redistribute check box and checking the Default Information Originate check box.

Step 5 Enter the IP address in the IP Address field of the network or host to be added to the area. Use 0.0.0.0 with a netmask of 0.0.0.0 to create the default area. You can only enter 0.0.0.0 in one area.

Step 6 Enter the network mask in the Network Mask field for the IP address or host to be added to the area. If adding a host, choose the 255.255.255.255 mask.

Step 7 In the Authentication area, click the None radio button to disable OSPF area authentication.

Step 8 Enter a value in the Default Cost field to specify a default cost for the OSPF area.

Valid values range from 0 to 65535. The default value is 1.

Step 9 Click OK.

Configuring an IP Address Pool for Clustering (OSPFv2 and OSPFv3)

You can assign a range of IPv4 addresses for the router ID cluster pool if you are using Individual Interface clustering.

To assign a range of IPv4 addresses for the router ID cluster pool in Individual Interface for OSPFv2, perform the following steps:

Step 1 From the main ASDM home page, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPF Process Advanced Properties dialog box appears.

Step 4 Click the Cluster Pool radio button. If you are using clustering, then you do not need to specify an IP address pool for the router ID (that is, leave the field blank). If you do not enter an IP address pool, then the ASA uses the automatically generated router ID.

Step 5 Enter the name of the IP address pool, or click the ellipses to display the Select IP Address Pool dialog box.

Step 6 Double-click an existing IP address pool name to add it to the Assign field. Alternatively, click Add to create a new IP address pool.

The Add IPv4 Pool dialog box appears.

Step 7 Enter the new IP address pool name in the Name field.

Step 8 Enter the starting IP address or click the ellipses to display the Browse Starting IP Address dialog box.

Step 9 Double-click an entry to add it to the Starting IP Address field, then click OK.

Step 10 Enter the ending IP address or click the ellipses to display the Browse Ending IP Address dialog box.

Step 11 Double-click an entry to add it to the Ending IP Address field, then click OK.

Step 12 Choose the subnet mask from the drop-down list, then click OK.

The new IP address pool appears in the Select IP Address Pool list.

Step 13 Double-click the new IP address pool name to add it to the Assign field, then click OK.

The new IP address pool name appears in the Cluster Pool field of the Edit OSPF Process Advanced Properties dialog box.

Step 14 Click OK.

Step 15 If you want to change the newly added IP address pool settings, click Edit.

The Edit IPv4 Pool dialog box appears.

Step 16 Repeat Steps 4 through 14.

Note You cannot edit or delete an existing IP address pool that has been assigned and is already being used by one or more connection profiles.

Step 17 Click OK.

To assign a range of IPv4 addresses for the router ID cluster pool in Individual Interface clustering for OSPFv3, perform the following steps:

Step 1 From the main ASDM home page, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 Choose the Cluster Pool option from the Router ID drop-down list. If you do not need to specify an IP address pool for the router ID, choose the Automatic option. If you do not configure an IP address pool, then the ASA uses the automatically generated router ID.

Step 5 Enter the IP address pool name. Alternatively, click the ellipses to display the Select IP Address Pool dialog box.

Step 6 Double-click an existing IP address pool name to add it to the Assign field. Alternatively, click Add to create a new IP address pool.

The Add IPv4 Pool dialog box appears.

Step 7 Enter the new IP address pool name in the Name field.

Step 8 Enter the starting IP address or click the ellipses to display the Browse Starting IP Address dialog box.

Step 9 Double-click an entry to add it to the Starting IP Address field, then click OK.

Step 10 Enter the ending IP address or click the ellipses to display the Browse Ending IP Address dialog box.

Step 11 Double-click an entry to add it to the Ending IP Address field, then click OK.

Step 12 Choose the subnet mask from the drop-down list, then click OK.

The new IP address pool appears in the Select IP Address Pool list.

Step 13 Double-click the new IP address pool name to add it to the Assign field, then click OK.

The new IP address pool name appears in the Cluster Pool field of the Edit OSPF Process Advanced Properties dialog box.

Step 14 Click OK.

Step 15 If you want to change the newly added cluster pool settings, click Edit.

The Edit IPv4 Pool dialog box appears.

Step 16 Repeat Steps 4 through 14.

Note You cannot edit or delete an existing IP address pool that has been assigned and is already being used by another OSPFv3 process.

Step 17 Click OK.

Defining Static OSPFv2 Neighbors

You need to define static OSPFv2 neighbors to advertise OSPFv2 routes over a point-to-point, non-broadcast network. This feature lets you broadcast OSPFv2 advertisements across an existing VPN connection without having to encapsulate the advertisements in a GRE tunnel.

Before you begin, you must create a static route to the OSPFv2 neighbor. See “Static and Default Routes,” for more information about creating static routes.

To define a static OSPFv2 neighbor, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Static Neighbor.

Step 2 Click Add or Edit.

The Add/Edit OSPF Neighbor Entry dialog box appears. This dialog box lets you define a new static neighbor or change information for an existing static neighbor. You must define a static neighbor for each point-to-point, nonbroadcast interface. Note the following restrictions:

• You cannot define the same static neighbor for two different OSPF processes.
• You need to define a static route for each static neighbor.

Step 3 From the OSPF Process drop-down list, choose the OSPF process associated with the static neighbor. If you are editing an existing static neighbor, you cannot change this value.

Step 4 In the Neighbor field, enter the IP address of the static neighbor.

Step 5 In the Interface field, choose the interface associated with the static neighbor. If you are editing an existing static neighbor, you cannot change this value.

Step 6 Click OK.

Configuring Route Calculation Timers

You can configure the delay time between when OSPFv2 receives a topology change and when it starts an SPF calculation. You also can configure the hold time between two consecutive SPF calculations.

To configure route calculation timers, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPF Process Advanced Properties dialog box appears.

Step 4 The Timers area allows you to modify the settings that are used to configure LSA pacing and SPF calculation timers. In the Timers area, enter the following values:

• The Initial SPF Delay, specifies the time (in milliseconds) between when OSPF receives a topology change and when the SPF calculation starts. Valid values range from 0 to 600000 milliseconds.
• The Minimum SPF Hold Time, specifies the hold time (in milliseconds)between consecutive SPF calculations.Valid values range from 0 to 600000 milliseconds.
• The Maximum SPF Wait Time, specifies the maximum wait time between two consecutive SPF calculations. Valid values range from 0 to 600000 milliseconds.

Step 5 Click OK.

Logging Neighbors Going Up or Down

By default, a syslog message is generated when an OSPFv2 neighbor goes up or down.

To log OSPFv2 neighbors going up or down, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Setup.

Step 2 Click the Process Instances tab.

Step 3 Click Advanced.

The Edit OSPF Process Advanced Properties dialog box appears.

Step 4 The Adjacency Changes area includes settings that define the adjacency changes that cause syslog messages to be sent. In the Adjacency Changes area, enter the following values:

• Check the Log Adjacency Changes check box to cause the ASA to send a syslog message whenever an OSPFv2 neighbor goes up or down. This setting is checked by default.
• Check the Log Adjacency Changes Detail check box to cause the ASA to send a syslog message whenever any state change occurs, not just when a neighbor goes up or down. This setting is unchecked by default.

Step 5 Click OK.

Note Logging must be enabled for the neighbor up or down messages to be sent.

Configuring Filtering in OSPF

The Filtering pane displays the ABR Type 3 LSA filters that have been configured for each OSPF process.

ABR Type 3 LSA filters allow only specified prefixes to be sent from one area to another area and restrict all other prefixes. This type of area filtering can be applied out of a specific OSPF area, into a specific OSPF area, or into and out of the same OSPF areas at the same time.

OSPF ABR Type 3 LSA filtering improves your control of route distribution between OSPF areas.

Note Only Type 3 LSAs that originate from an ABR are filtered.

To configure filtering in OSPF, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Filtering.

Step 2 Click Add or Edit.

The Add or Edit OSPF Filtering Entry dialog box lets you add new filters to the Filter table or modify an existing filter. Some of the filtering information cannot be changed when you edit an existing filter.

Step 3 Choose the OSPF process that is associated with the filter entry from the OSPF Process drop-down list.

Step 4 Choose the Area ID that is associated with the filter entry from the Area ID drop-down list. If you are editing an existing filter entry, you cannot modify this setting.

Step 5 Choose a prefix list from the Prefix List drop-down list.

Step 6 Choose the traffic direction being filtered from the Traffic Direction drop-down list.

Choose Inbound to filter LSAs coming into an OSPF area, or Outbound to filter LSAs coming out of an OSPF area. If you are editing an existing filter entry, you cannot modify this setting.

Step 7 Click Manage to display the Configure Prefix Lists dialog box, from which you can add, edit, or delete prefix lists and prefix rules. For more information, see Configuring Prefix Lists and the Configuring the Metric Values for a Route Action.

Step 8 Click OK.

Configuring a Virtual Link in OSPF

If you add an area to an OSPF network, and it is not possible to connect the area directly to the backbone area, you need to create a virtual link. A virtual link connects two OSPF devices that have a common area, called the transit area. One of the OSPF devices must be connected to the backbone area.

To define new virtual links or change the properties of existing virtual links, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPF > Virtual Link.

Step 2 Click Add or Edit.

The Add or Edit OSPF Virtual Link dialog box appears, which allows you to define new virtual links or change the properties of existing virtual links.

Step 3 Choose the OSPF process ID that is associated with the virtual link from the OSPF Process drop-down list. If you are editing an existing virtual link entry, you cannot modify this setting.

Step 4 Choose the Area ID that is associated with the virtual link from the Area ID drop-down list.

Choose the area shared by the neighbor OSPF devices. The selected area cannot be an NSSA or a Stub area. If you are editing an existing virtual link entry, you cannot modify this setting.

Step 5 In the Peer Router ID field, enter the router ID of the virtual link neighbor.

If you are editing an existing virtual link entry, you cannot modify this setting.

Step 6 Click Advanced to edit advanced virtual link properties,

The Advanced OSPF Virtual Link Properties dialog box appears. You can configure the OSPF properties for the virtual link in this area. These properties include authentication and packet interval settings.

Step 7 In the Authentication area, choose the Authentication type by clicking the radio button next to one of the following options:

• None to disable OSPF authentication.
• Authentication Password to use clear text password authentication. This is not recommended where security is a concern.
• MD5 to use MD5 authentication (recommended).
• Area (Default) to use the authentication type specified for the area. See Configuring OSPFv2 Area Parameters for information about configuring area authentication. Area authentication is disabled by default. Therefore, unless you have previously specified an area authentication type, interfaces set to area authentication have authentication disabled until you configure this setting.

Step 8 In the Authentication Password area, enter and re-enter a password when password authentication is enabled. Passwords must be a text string of up to 8 characters.

Step 9 In the MD5 IDs and Key area, enter the MD5 keys and parameters when MD5 authentication is enabled. All devices on the interface using OSPF authentication must use the same MD5 key and ID. Specify the following settings:

a. In the Key ID field, enter a numerical key identifier. Valid values range from 1 to 255. The Key ID displays for the selected interface.

b. In the Key field, enter an alphanumeric character string of up to 16 bytes. The Key ID displays for the selected interface.

c. Click Add or Delete to add or delete the specified MD5 key to the MD5 ID and Key table.

Step 10 In the Interval area, specify the interval timing for the packet by choosing from the following options:

• Hello Interval to specify the interval, in seconds, between hello packets sent on an interface. The smaller the hello interval, the faster topological changes are detected, but the more traffic is sent on the interface. This value must be the same for all routers and access servers on a specific interface. Valid values range from 1 to 65535 seconds. The default value is 10 seconds.
• Retransmit Interval to specify the time, in seconds, between LSA retransmissions for adjacencies belonging to the interface. When a router sends an LSA to its neighbor, it keeps the LSA until it receives the acknowledgement message. If the router receives no acknowledgement, it will resend the LSA. Be conservative when setting this value, or needless retransmission can result. The value should be larger for serial lines and virtual links. Valid values range from 1 to 65535 seconds. The default value is 5 seconds.
• Transmit Delay to specify the estimated time, in seconds, required to send an LSA packet on the interface. LSAs in the update packet have their ages increased by the amount specified by this field before transmission. If the delay is not added before transmission over a link, the time in which the LSA propagates over the link is not considered. The value assigned should take into account the transmission and propagation delays for the interface. This setting has more significance on very low-speed links. Valid values range from 1 to 65535 seconds. The default value is 1 second.
• Dead Interval to specify the interval, in seconds, in which no hello packets are received, causing neighbors to declare a router down. Valid values range from 1 to 65535. The default value of this field is four times the interval set by the Hello Interval field.

Step 11 Click OK.

Enabling OSPFv3

To enable OSPFv3, you need to create an OSPFv3 routing process, create an area for OSPFv3, enable an interface for OSPFv3, then redistribute the route into the targeted OSPFv3 routing processes.

To enable OSPFv3, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 On the Process Instances tab, check the Enable OSPFv3 Process check box. You can enable up to two OSPF process instances. Only single context mode is supported.

Step 3 Enter a process ID in the Process ID field. The ID can be any positive integer.

Step 4 Click Apply to save your changes.

Step 5 To continue, see Configuring OSPFv3 Area Parameters.

Configuring OSPFv3 Interface Parameters

You can change certain interface-specific OSPFv3 parameters, if necessary. You are not required to change any of these parameters, but the following interface parameters must be consistent across all routers in an attached network: the hello interval and the dead interval. If you configure any of these parameters, be sure that the configurations for all routers on your network have compatible values.

To configure OSPFv3 interface parameters for IPv6, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Interfaces.

Step 2 Click the Authentication tab.

Step 3 To specify the authentication parameters for an interface, select the interface and click Edit.

The Edit OSPFv3 Interface Authentication dialog box appears.

Step 4 Choose the authentication type from the Authentication Type drop-down list. The available options are Area, Interface, and None. The None option indicates that no authentication is used.

Step 5 Choose the authentication algorithm from the Authentication Algorithm drop-down list. Supported values are SHA-1 and MD5.

Step 6 Enter the authentication key in the Authentication Key field. When MD5 authentication is used, the key must be 32 hexadecimal digits (16 bytes) long. When SHA-1 authentication is used, the key must be 40 hexadecimal digits (20 bytes) long.

Step 7 Choose the encryption algorithm from the Encryption Algorithm drop-down list. Supported values are AES-CDC, 3DES, and DES. The NULL entry indicates no encryption.

Step 8 Enter the encryption key in the Encryption Key field.

Step 9 Click OK.

Step 10 Click the Properties tab.

Step 11 Select the interface whose properties you want to modify, and click Edit.

The Edit OSPFv3 Interface Properties dialog box appears.

Step 12 Check the Enable OSPFv3 on this interface check box.

Step 13 Choose the process ID from the drop-down list.

Step 14 Choose the area ID from the drop-down list.

Step 15 (Optional) Specify the area instance ID to be assigned to the interface. An interface can have only one OSPFv3 area. You can use the same area on multiple interfaces, and each interface can use a different area instance ID.

Step 16 Choose the network type from the drop-down list. Supported options are Default, Broadcast, and Point-to-Point.

Step 17 Enter the cost of sending a packet on an interface in the Cost field.

Step 18 Enter the router priority, which helps determine the designated router for a network. in the Priority field. Valid values range from 0 to 255.

Step 19 Check the Disable MTU mismatch detection check box to disable the OSPF MTU mismatch detection when DBD packets are received. OSPF MTU mismatch detection is enabled by default.

Step 20 Check the Filter outgoing link state advertisements check box to filter outgoing LSAs to an OSPFv3 interface. All outgoing LSAs are flooded to the interface by default.

Step 21 In the Timers area, in the Dead Interval field, enter the time period in seconds for which hello packets must not be seen before neighbors indicate that the router is down. The value must be the same for all nodes on the network and can range from 1 to 65535.

Step 22 In the Hello Interval field, enter the interval in seconds between hello packets sent on the interface. The value must be the same for all nodes on a specific network and can range from 1 to 65535. The default interval is 10 seconds for Ethernet interfaces and 30 seconds for non-broadcast interfaces.

Step 23 In the Retransmit Interval field, enter the time in seconds between LSA retransmissions for adjacencies that belong to the interface. The time must be greater than the expected round-trip delay between any two routers on the attached network. Valid values range from 1 to 65535 seconds. The default is 5 seconds.

Step 24 In the Transmit Delay field, enter the estimated time in seconds to send a link-state update packet on the interface. Valid values range from 1 to 65535 seconds. The default is 1 second.

Step 25 Click OK.

Step 26 Click Apply to save your changes.

Configuring OSPFv3 Area Parameters

To configure OSPFv3 area parameters, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Areas tab.

Step 3 To add a new area, click Add. To modify an existing area, click Edit. To remove a selected area, click Delete.

The Add OSPFv3 Area dialog box or Edit OSPFv3 Area dialog box appears.

Step 4 From the OSPFv3 Process ID drop-down list, choose the process ID.

Step 5 Enter the area ID, which specifies the area for which routes are to be summarized, in the Area ID field.

Step 6 Choose the area type from the Area Type drop-down list. Available options are Normal, NSSA, and Stub.

Step 7 To allow the sending of summary LSAs into the area, check the Allow sending of summary LSAs into the area check box.

Step 8 To allow redistribution to import routes to normal and not so stubby areas, check the Redistribution imports routes to normal and NSSA areas check box.

Step 9 To generate a default external route into an OSPFv3 routing domain, check the Default information originate check box.

Step 10 Enter the metric used for generating the default route in the Metric field. The default value is 10. Valid metric values range from 0 to 16777214.

Step 11 Choose the metric type from the Metric Type drop-down list. The metric type is the external link type that is associated with the default route that is advertised into the OSPFv3 routing domain. The available options are 1 for a Type 1 external route or 2 for a Type 2 external route.

Step 12 Enter the cost in the Default Cost field.

Step 13 Click OK.

Step 14 Click the Route Summarization tab.

Step 15 To specify a new range for consolidating and summarizing routes, click Add. To modify an existing range for consolidating and summarizing routes, click Edit.

The Add Route Summarization dialog box or Edit Route Summarization dialog box appears.

Step 16 Choose the process ID from the Process ID drop-down list.

Step 17 Choose the area ID from the Area ID drop-down list.

Step 18 Enter the IPv6 prefix and prefix length in the IPv6 Prefix/Prefix Length field.

Step 19 (Optional) Enter the metric or cost for the summary route, which is used during OSPF SPF calculations to determine the shortest paths to the destination. Valid values range from 0 to 16777215.

Step 20 Check the Advertised check box to set the address range status to advertised and generate a Type 3 summary LSA.

Step 21 Click OK.

Step 22 To continue, see Configuring a Virtual Link Neighbor.

Configuring a Virtual Link Neighbor

To configure a virtual link neighbor, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Virtual Link.

Step 2 To add a new virtual link neighbor, click Add. To modify an existing virtual link neighbor, click Edit. To remove a selected virtual link neighbor, click Delete.

The Add Virtual Link dialog box or Edit Virtual Link dialog box appears.

Step 3 Choose the process ID from the Process ID drop-down list.

Step 4 Choose the area ID from the Area ID drop-down list.

Step 5 Enter the peer router ID (that is, the IP address) in the Peer Router ID field.

Step 6 (Optional) Enter the time-to-live (TTL) security hop count on a virtual link in the TTL Security field. The hop count value can range from 1 to 254.

Step 7 In the Timers area, enter the time in seconds that hello packets are not seen before a neighbor indicates that the router is down in the Dead Interval field. The dead interval is an unsigned integer. The default is four times the hello interval, or 40 seconds. The value must be the same for all routers and access servers that are attached to a common network. Valid values range from 1 to 8192.

Step 8 Enter the time in seconds between the hello packets that are sent on an interface in the Hello Interval field. The hello interval is an unsigned integer that is to be advertised in the hello packets. The value must be the same for all routers and access servers that are attached to a common network. Valid values range from 1 to 8192. The default is 10.

Step 9 Enter the time in seconds between LSA retransmissions for adjacencies that belong to the interface in the Retransmit Interval field. The retransmit interval is the expected round-trip delay between any two routers on the attached network. The value must be greater than the expected round-trip delay, and can range from 1 to 8192. The default is 5.

Step 10 Enter the estimated time in seconds that is required to send a link-state update packet on the interface in the Transmit Delay field. The integer value must be greater than zero. LSAs in the update packet have their own ages incremented by this amount before transmission. The range of values can be from 1 to 8192. The default is 1.

Step 11 In the Authentication area, check the Enable Authentication check box to enable authentication.

Step 12 Enter the security policy index, which must be a number from 256 to 4294967295, in the Security Policy Index field.

Step 13 Choose the authentication algorithm from the Authentication Algorithm drop-down list. Supported values are SHA-1 and MD5. When MD5 authentication is used, the key must be 32 hexadecimal digits (16 bytes) long. When SHA-1 authentication is used, the key must be 40 hexadecimal digits (20 bytes) long.

Step 14 Enter the authentication key in the Authentication Key field. The key must include 32 hexadecimal characters.

Step 15 Choose the encryption algorithm from the Encryption Algorithm drop-down list. Supported values are AES-CDC, 3DES, and DES. The NULL entry indicates no encryption.

Step 16 Enter the encryption key in the Encryption Key field.

Step 17 Click OK.

Step 18 Click Apply to save your changes.

Configuring OSPFv3 Passive Interfaces

To configure OSPFv3 passive interfaces, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPFv3 process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 The Passive Interfaces area allows you to enable passive OSPFv3 routing on an interface. Passive routing assists in controlling the advertisement of OSPFv3 routing information and disables the sending and receiving of OSPFv3 routing updates on an interface. In the Passive Interfaces area, choose the following settings:

• Check the Global passive check box to make all of the interfaces listed in the table passive. Uncheck individual interfaces to make them non-passive.
• Uncheck the Global passive check box to make all of the interfaces non-passive. Check individual interfaces to make them passive.

Step 5 Click OK.

Step 6 Click Apply to save your changes.

Configuring OSPFv3 Administrative Distance

To configure OSPFv3 administrative distance for IPv6 routes, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

The Administrative Route Distances area allows you to modify the settings that were used to configure administrative route distances. The administrative route distance is an integer from 10 to 254. In the Administrative Route Distances area, enter the following values:

• The Inter Area, which specifies the inter-area routes for OSPV for IPv6 routes.
• The Intra Area, which specifies the intra-area routes for OSPF for IPv6 routes.
• The External, which specifies the external type 5 and type 7 routes for OSPF for IP6 routes.

Step 4 Click OK.

Step 5 Click Apply to save your changes.

Configuring OSPFv3 Timers

You can set LSA arrival, LSA pacing, and throttling timers for OSPFv3.

To set the minimum interval at which the ASA accepts the same LSA from OSPFv3 neighbors, perform the following steps:

To configure LSA flood packet pacing, perform the following steps:

To change the interval at which OSPFv3 LSAs are collected into a group and refreshed, check summed, or aged, perform the following steps:

To configure LSA retransmission packet pacing, perform the following steps:

LSA and SPF throttling provide a dynamic mechanism to slow down LSA updates in OSPFv3 during times of network instability and allow faster OSPFv3 convergence by providing LSA rate limiting in milliseconds.

To configure LSA and SPF throttling timers, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPFv3 process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 The Timers area allows you to modify the settings that are used to configure LSA arrival, LSA pacing, LSA retransmission, LSA throttle, and SPF throttle times. In the Timers area, enter the following values:

• The LSA Arrival, which specifies the minimum delay in milliseconds that must pass between acceptance of the same LSA arriving from neighbors. The range is from 0 to 6000,000 milliseconds. The default is 1000 milliseconds.
• The LSA Flood Pacing, which specifies the time in milliseconds at which LSAs in the flooding queue are paced in between updates. The configurable range is from 5 to 100 milliseconds. The default value is 33 milliseconds.
• The LSA Group Pacing, which specifies the interval in seconds at which LSAs are collected into a group and refreshed, check summed, or aged. Valid values range from 10 to 1800. The default value is 240.
• The LSA Retransmission Pacing, which specifies the time in milliseconds at which LSAs in the retransmission queue are paced. The configurable range is from 5 to 200 milliseconds. The default value is 66 milliseconds.
• The LSA Throttle Initial, which specifies the delay in milliseconds to generate the first occurrence of the LSA. The default value is 0 milliseconds.
• The LSA Throttle Min Hold, which specifies the minimum delay in milliseconds to originate the same LSA. The default value is 5000 milliseconds.
• The LSA Throttle Max Wait, which specifies the maximum delay in milliseconds to originate the same LSA. The default value is 5000 milliseconds.

Note For LSA throttling, if the minimum or maximum time is less than the first occurrence value, then OSPFv3 automatically corrects to the first occurrence value. Similarly, if the maximum delay specified is less than the minimum delay, then OSPFv3 automatically corrects to the minimum delay value.

• The SPF Throttle Initial, specifies the delay in milliseconds to receive a change to the SPF calculation. The default value is 5000 milliseconds.
• The SPF Throttle Min Hold, which specifies the delay in milliseconds between the first and second SPF calculations. The default value is 10000 milliseconds.
• The SPF Throttle Max Wait, which specifies the maximum wait time in milliseconds for SPF calculations. The default value is 10000 milliseconds.

Note For SPF throttling, if the minimum or maximum time is less than the first occurrence value, then OSPFv3 automatically corrects to the first occurrence value. Similarly, if the maximum delay specified is less than the minimum delay, then OSPFv3 automatically corrects to the minimum delay value.

Step 5 Click OK.

Step 6 Click Apply to save your changes.

Defining Static OSPFv3 Neighbors

You need to define static OSPFv3 neighbors to advertise OSPF routes over a point-to-point, non-broadcast network. This feature lets you broadcast OSPFv3 advertisements across an existing VPN connection without having to encapsulate the advertisements in a GRE tunnel.

Before you begin, you must create a static route to the OSPFv3 neighbor. See “Static and Default Routes,” for more information about creating static routes.

To define a static OSPFv3 neighbor, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Static Neighbor.

Step 2 Click Add or Edit.

The Add or Edit Static Neighbor dialog box appears. This dialog box lets you define a new static neighbor or change information for an existing static neighbor. You must define a static neighbor for each point-to-point, nonbroadcast interface. Note the following restrictions:

• You cannot define the same static neighbor for two different OSPFv3 processes.
• You need to define a static route for each static neighbor.

Step 3 From the Interface drop-down list, choose the interface associated with the static neighbor. If you are editing an existing static neighbor, you cannot change this value.

Step 4 In the Link-local Address field, enter the IPv6 address of the static neighbor.

Step 5 (Optional) In the Priority field, enter the priority level.

Step 6 (Optional) In the Poll Interval field, enter the poll interval in seconds.

Step 7 Click OK.

Sending Syslog Messages

To configure the router to send a syslog message when an OSPFv3 neighbor goes up or down, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

The Adjacency Changes area allows you to modify the settings for sending syslog messages when an OSPFv3 neighbor goes up or down. In the Adjacency Changes area, do the following:

• To send a syslog message when an OSPFv3 neighbor goes up or down, check the Log Adjacency Changes check box.
• To sends a syslog message for each state, not only when an OSPFv3 neighbor goes up or down, check the Include Details check box.

Step 4 Click OK.

Step 5 Click Apply to save your changes.

Suppressing Syslog Messages

To suppress the sending of syslog messages when the route receives unsupported LSA Type 6 multicast OSPF (MOSPF) packets, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPFv3 process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 Check the Ignore LSA MOSPF check box, then click OK.

Calculating Summary Route Costs

To calculate summary route costs according to RFC 1583, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPF process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 Check the RFC1583 Compatible check box, then click OK.

Generating a Default External Route into an OSPFv3 Routing Domain

To generate a default route into an OSPFv3 routing domain, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Setup.

Step 2 Click the Process Instances tab.

Step 3 Choose the OSPFv3 process that you want to edit, then click Advanced.

The Edit OSPFv3 Process Advanced Properties dialog box appears.

Step 4 In the Default Information Originate Area, do the following:

a. Check the Enable check box to enable the OSPFv3 routing process.

b. Check the Always advertise check box to always advertise the default route, whether or not one exists.

c. Enter the metric used for generating the default route in the Metric field. Valid metric values range from 0 to 16777214. The default value is 10.

d. From the Metric Type drop-down list, choose the external link type that is associated with the default route that is advertised into the OSPFv3 routing domain. Valid values are the following:

• 1—Type 1 external route
• 2—Type 2 external route

The default is the Type 2 external route.

e. From the Route Map drop-down list, choose the routing process that generates the default route if the route map is satisfied.

Step 5 Click OK.

Step 6 Click Apply to save your changes.

Configuring an IPv6 Summary Prefix

To configure an IPv6 summary prefix, perform the following steps:

Step 1 In the ASDM main window, choose Configuration > Device Setup > Routing > OSPFv3 > Summary Prefix.

Step 2 To add a new summary prefix, click Add. To modify an existing summary prefix, click Edit. To remove a summary prefix, click Delete.

The Add Summary Prefix dialog box or Edit Summary Prefix dialog box appears.

Step 3 Choose the process ID from the Process ID drop-down list.

Step 4 Enter the IPv6 prefix and prefix length in the IPv6 Prefix/Prefix Length field.

Step 5 Check the Advertise check box to advertise routes that match the specified prefix and mask pair. Uncheck this check box to suppress routes that match the specified prefix and mask pair.

Step 6 Enter the tag value that you can use as a match value for controlling redistribution through route maps in the Tag field.

Step 7 Click OK.

Step 8 Click Apply to save your changes.

Redistributing IPv6 Routes

To redistribute connected routes into an OSPFv3 process, perform the following steps:

Step 1 In the main ASDM window, choose Configuration > Device Setup > Routing > OSPFv3 > Redistribution.

Step 2 To add new parameters for redistributing connected routes into an OSPFv3 process, click Add. To modify existing parameters for redistributing connected routes into an OSPFv3 process, click Edit. To remove a selected set of parameters, click Delete.

The Add Redistribution dialog box or Edit Redistribution dialog box appears.

Step 3 Choose the process ID from the Process ID drop-down list.

Step 4 Choose the source protocol from which routes are being redistributed from the Source Protocol drop-down list. The supported protocols are connected, static, and OSPF.

Step 5 Enter the metric value in the Metric field. When redistributing routes from one OSPF process into another OSPF process on the same router, the metric is carried through from one process to the other if no metric value is specified. When redistributing other processes into an OSPF process, the default metric is 20 when no metric value is specified.

Step 6 Choose the metric type from the Metric Type drop-down list. The available options are None, 1, and 2.

Step 7 (Optional) Enter the tag value in the Tag field. This parameter specifies the 32-bit decimal value attached to each external route, which may be used to communicate information between ASBRs. If none is specified, then the remote autonomous system number is used for routes from BGP and EGP. For other protocols, zero is used. Valid values are from 0 to 4294967295.

Step 8 Choose the route map from the Route Map drop-down list to check for filtering the importing of routes from the source routing protocol to the current routing protocol. If this parameter is not specified, all routes are redistributed. If this parameter is specified, but no route map tags are listed, no routes are imported.

Step 9 To include connected routes in the redistribution, check the Include connected check box.

Step 10 Check the Match check box to redistribute routes into other routing domains, then check one of the following check boxes:

• Internal for routes that are internal to a specific autonomous system
• External 1 for routes that are external to the autonomous system, but are imported into OSPFv3 as Type 1 external routes
• External 2 for routes that are external to the autonomous system, but are imported into OSPFv3 as Type 2 external routes
• NSSA External 1 for routes that are external to the autonomous system, but are imported into OSPFv3 in an NSSA for IPv6 as Type 1 external routes
• NSSA External 2 for routes that are external to the autonomous system, but are imported into OSPFv3 in an NSSA for IPv6 as Type 2 external routes

Step 11 Click OK.

Step 12 Click Apply to save your changes.

RFCs