Cisco IAD880 Integrated Access Devices Software Configuration Guide - Configuring the Ethernet Switches [Cisco IAD880 Series Integrated Access Devices]

Table Of Contents

Configuring Ethernet Switches

Switch Port Numbering and Naming

Restrictions for the FE Switch

Information About Ethernet Switches

VLANs and VLAN Trunk Protocol

Inline Power

Layer 2 Ethernet Switching

802.1x Authentication

Spanning Tree Protocol

Cisco Discovery Protocol

Switched Port Analyzer

IGMP Snooping

Storm Control

Overview of SNMP MIBs

BRIDGE-MIB for Layer 2 Ethernet Switching

MAC Address Notification

How to Configure Ethernet Switches

Configuring VLANs

VLANs on the FE and GE Switch Ports

VLANs on the GE Port and GE ESW Port of Wireless APs

Configuring Layer 2 Interfaces

Configuring 802.1x Authentication

Configuring Spanning Tree Protocol

Configuring MAC Table Manipulation

Configuring Cisco Discovery Protocol

Configuring the Switched Port Analyzer

Configuring Power Management on the Interface

Configuring IP Multicast Layer 3 Switching

Configuring IGMP Snooping

Configuring Per-Port Storm Control

Configuring Separate Voice and Data Subnets

Managing the Switch

Configuring Ethernet Switches

This chapter gives an overview of configuration tasks for the following:

•4-port Fast Ethernet (FE) switch on the Cisco 860, 880, and 890 integrated service routers (ISRs)

•Gigabit Ethernet (GE) switch on the Cisco 860VAE-K9

•Gigabit Ethernet (GE) switch that services the embedded wireless access point on the Cisco 860 and Cisco 880 series ISRs.

The FE switches are 10/100Base T Layer 2 Fast Ethernet switches. The GE switch is a 1000Base T Layer 2 Gigabit Ethernet switch. Traffic between different VLANs on a switch is routed through the router platform with the switched virtual interface (SVI).

Any switch port may be configured as a trunking port to connect to other Cisco Ethernet switches.

An optional power module can be added to Cisco 880 series ISRs to provide inline power to two of the FE ports for IP telephones or external access points.

This chapter contains the following sections:

•Switch Port Numbering and Naming

•Restrictions for the FE Switch

•Information About Ethernet Switches

•Overview of SNMP MIBs

•How to Configure Ethernet Switches

Switch Port Numbering and Naming

The ports for Cisco 860, 880, and 890 ISRs are numbered as follows:

•The ports on the FE switch for the Cisco 860, 880, and 890 ISRs are numbered FE0 through FE3.

•The port on the GE switch for the 860VAE-K9 is numbered GE0.

•The port on the GE switch that services the embedded wireless access point on the Cisco 860 and Cisco 880 series ISRs is named and numbered Wlan-GigabitEthernet0.

Restrictions for the FE Switch

The following restrictions apply to the FE switch:

•Ports of an FE switch must not be connected to any Fast Ethernet onboard port of the router.

•On Cisco 880 series ISRs, inline power is supported only on FE switch ports FE0 and FE1. Inline power is not supported on Cisco 860 series ISRs.

•VTP pruning is not supported.

•FE switch can support up to 200 secure MAC addresses.

Information About Ethernet Switches

To configure Ethernet switches, you should understand the following concepts:

•VLANs and VLAN Trunk Protocol

•Inline Power

•Layer 2 Ethernet Switching

•802.1x Authentication

•Spanning Tree Protocol

•Cisco Discovery Protocol

•Switched Port Analyzer

•IGMP Snooping

•Storm Control

VLANs and VLAN Trunk Protocol

For information on the concepts of VLANs and VLAN Trunk Protocol (VTP), see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1047027

Inline Power

Inline power is not supported on the Cisco 860 series ISRs. On the Cisco 880 series ISRs, inline power can be supplied to Cisco IP phones or external access points on FE switch ports FE0 and FE1.

A detection mechanism on the FE switch determines whether it is connected to a Cisco device. If the switch senses that there is no power on the circuit, the switch supplies the power. If there is power on the circuit, the switch does not supply it.

You can configure the switch to never supply power to the Cisco device and to disable the detection mechanism.

The FE switch also provides support for powered devices compliant with IEEE 802.3af.

Layer 2 Ethernet Switching

For information on Layer 2 Ethernet Switching, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1048478

802.1x Authentication

For information on 802.1x Authentication, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1051006

Note The authentication command under switch trunk interface mode is enabled for the NEAT feature. This is available with Cisco IOS Release 15.2T.

Spanning Tree Protocol

For information on Spanning Tree Protocol, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1048458

Cisco Discovery Protocol

Cisco Discovery Protocol (CDP) runs over Layer 2 (the data link layer) on all Cisco routers, bridges, access servers, and switches. CDP allows network management applications to discover Cisco devices that are neighbors of already known devices, in particular, neighbors running lower-layer, transparent protocols. With CDP, network management applications can learn the device type and the SNMP agent address of neighboring devices. This feature enables applications to send SNMP queries to neighboring devices.

CDP runs on all LAN and WAN media that support Subnetwork Access Protocol (SNAP). Each CDP-configured device sends periodic messages to a multicast address. Each device advertises at least one address at which it can receive SNMP messages. The advertisements also contain the time-to-live, or hold-time information, which indicates the length of time a receiving device should hold CDP information before discarding it.

Switched Port Analyzer

For information on Switched Port Analyzer, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1053663

IGMP Snooping

For information on IGMP Snooping, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1053727

IGMP Version 3

The Cisco 880 series ISRs support Version 3 of IGMP snooping.

IGMPv3 provides support for source filtering, which enables a multicast receiver host to signal to a router from which groups the receiver host is to receive multicast traffic, and from which sources this traffic is expected. Enabling the IGMPv3 feature with IGMP snooping on Cisco ISRs provides Basic IGMPv3 Snooping Support (BISS). BISS provides constrained flooding of multicast traffic in the presence of IGMPv3 hosts. This support constrains traffic to approximately the same set of ports as IGMPv2 snooping does with IGMPv2 hosts. The constrained flooding only considers the destination multicast address.

Storm Control

For information on storm control, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gt1636nm.html#wp1051018

Overview of SNMP MIBs

Simple Management Network Protocol (SNMP) development and use is centered around the MIB. An SNMP MIB is an abstract database and it is a conceptual specification for information that a management application may read and modify in a certain form. This does not imply that the information is kept in the managed system in that same form. The SNMP agent translates between the internal data structures and formats of the managed system and the external data structures and formats defined for the MIB.

The SNMP MIB is conceptually a tree structure with conceptual tables. Cisco Layer 2 Switching Interface MIB is discussed in more detail in BRIDGE-MIB for Layer 2 Ethernet Switching. Relative to this tree structure, the term MIB is used in two ways. One definitions of MIB is, it is actually a MIB branch, usually containing information for a single aspect of technology, such as a transmission medium or a routing protocol. A MIB used in this sense is more accurately called a MIB module, and is usually defined in a single document. The other definition of a MIB is a collection of such branches. Such a collection might comprise, for example, all the MIB modules implemented by a given agent, or the entire collection of MIB modules defined for SNMP.

A MIB is a tree where the leaves are individual items of data called objects. An object may be, for example, a counter or a protocol status. MIB objects are also sometimes called variables.

BRIDGE-MIB for Layer 2 Ethernet Switching

The Layer 2 Ethernet Switching Interface BRIDGE-MIB is supported in the Cisco 887, 880, and 890 platforms. The BRIDGE-MIB enables the user to know the Media Access Control (MAC) addresses and spanning tree information of the Ethernet switch modules. The user can query the MIB agent using the SNMP protocol and get the details of Ethernet switch modules, such as MAC addresses, of each interface and spanning protocol information.

The Bridge-MIB uses the following approaches to get the Layer 2 BRIDGE-MIB information:

•Community-string-based approach

•Context-based approach

In the community string based approach, one community string is created for each VLAN. Based on the query, the respective VLAN MIB is displayed.

To get the BRIDGE-MIB details, use the snmp-server community public RW command in the configuration mode.

Router(config)# snmp-server community public RW

Use the following syntax to query the SNMP BRIDGE-MIB details:
snmpwalk -v2c <ip address of the ISR, ...>  public .1.3.6.1.2.1.17
snmpwalk -v2c <ip address of the ISR, ...>  public@2 .1.3.6.1.2.1.17
snmpwalk -v2c <ip address of the ISR, ...>  public@3 .1.3.6.1.2.1.17
Note When you create a VLAN `x', the logical entity public@x is added. If you query with public community, the Layer 3 MIB is displayed. When you query with public@x, the Layer 2 MIB for VLAN `x' is displayed.

In the context based approach, the SNMP context mapping commands are used to display the values for Layer 2 interfaces. Each VLAN is mapped to a context. When the user queries with a context, the MIB displays the data for that specific VLAN, which is mapped to the context. In this approach, each VLAN is manually mapped to a context.

To get the BRIDGE-MIB details, use the following commands in the configuration mode:
Router(config)# Routersnmp-server group public v2c context bridge-group
Router(config)# snmp-server community public RW
Router(config)# snmp-server community private RW
Router(config)# snmp-server context bridge-group
Router(config)# snmp mib community-map public context bridge-group
Use the following syntax to query the SNMP BRIDGE-MIB details.
snmpwalk -v2c <ip address of the ISR, ...>  public@1 .1.3.6.1.2.1.17 ?L2-MIB
snmpwalk -v2c <ip address of the ISR, ...>  private .1.3.6.1.2.1.17?L3-MIB
Note When you query with the public community, the Layer 2 MIB is displayed. Use a private group for Layer 3 MIB.

For more details to configure and retrieve the BRIDGE-MIB details, see:

http://www.cisco.com/en/US/tech/tk648/tk362/technologies_tech_note09186a0080094a9b.
shtml#brgmib

MAC Address Notification

MAC address notification enables you to track users on a network by storing the MAC address activity on the switch. Whenever the switch learns or removes a MAC address, an SNMP notification can be generated and sent to the NMS. If you have many users coming and going from the network, you can set a trap interval time to bundle the notification traps and reduce network traffic. The MAC notification history table stores the MAC address activity for each hardware port for which the trap is enabled. MAC address notifications are generated for dynamic and secure MAC addresses; events are not generated for self addresses, multicast addresses, or other static addresses.

For more details to configure MAC address notification, see:

http://www1.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.2_25_see/
configuration/guide/swadmin.html#wp1102213

How to Configure Ethernet Switches

See the following sections for configuration tasks for Ethernet switches:

•Configuring VLANs

•Configuring Layer 2 Interfaces

•Configuring 802.1x Authentication

•Configuring Spanning Tree Protocol

•Configuring MAC Table Manipulation

•Configuring Cisco Discovery Protocol

•Configuring the Switched Port Analyzer

•Configuring Power Management on the Interface

•Configuring IP Multicast Layer 3 Switching

•Configuring IGMP Snooping

•Configuring Per-Port Storm Control

•Configuring Separate Voice and Data Subnets

•Managing the Switch

Configuring VLANs

This section provides information on how to configure VLANs. The Cisco 860 series ISRs support two VLANs and the 860VAE series ISRs support five VLANs.The Cisco 880 series ISRs support eight VLANs.

•VLANs on the FE and GE Switch Ports

•VLANs on the GE Port and GE ESW Port of Wireless APs

Note Cisco 866VAE-K9 and 867VAE-K9 routers have four Fast Ethernet (FE) switching ports and one Gigabit Ethernet (GE) switching port.

VLANs on the FE and GE Switch Ports

To configure VLANs, perform these steps, beginning in configuration mode.

SUMMARY STEPS

1. interface type number

2. shutdown

3. switchport access vlan vlan_id

4. no shutdown

5. end

DETAILED STEPS
Command or Action

Purpose
Step 1
interface type number

Example:
Router(config)# Interface fastethernet0
Selects the Fast Ethernet port to configure.
Step 2
shutdown

Example:
Router(config-if)# shutdown
(Optional) Shuts down the interface to prevent traffic flow until configuration is complete.
Step 3
switchport access vlan vlan_id

Example:
Router(config-if)# switchport access vlan 2
Creates instances of additional VLANs. Allowable values of vlan_id are 2 to 4094, except for reserved values of 1002 to 1005.
Step 4
no shutdown

Example:
Router(config-if)# no shutdown
Enables the interface, changing its state from administratively down to administratively up.
Step 5
end

Example:
Router(config-if)# end
Exits configuration mode.
For additional information, see the information at the following URL:

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/configuration/guide/
layer2.html

VLANs on the GE Port and GE ESW Port of Wireless APs

Because the GE port is an internal interface that services only the embedded access point of the router, it cannot be configured only with the switchport access vlan X command, where X is other than 1. It may, however, be configured in trunk mode. This may be done by performing the following steps, beginning in global configuration mode.

SUMMARY STEPS

1. interface type number

2. switchport mode trunk

3. switchport access vlan vlan_id

DETAILED STEPS
Comand or Action

Purpose
Step 1
interface type number

Example:
Router(config)# Interface gigabitethernet0
Selects the Gigabit Ethernet port to configure.
Step 2
switchport mode trunk

Example:
Router(config-if)# switchport mode trunk
Places the port in trunk mode.
Step 3
switchport access vlan vlan_id

Example:
Router(config-if)# switchport access vlan 2
(Optional) Once the port is in trunk mode, it may be assigned a VLAN number other than 1.
Configuring Layer 2 Interfaces

For information on how to configure Layer 2 interfaces, see the following URL:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1047041

The URL contains information on the following topics:

•Configuring a range of interfaces

•Defining a range macro

•Configuring Layer 2 optional interface features

Configuring 802.1x Authentication

For information on how to configure 802.1x port-based authentication, see:

http://www.cisco.com/en/US/docs/ios/12_4t/12_4t11/ht_8021x.html

The document contains information on the following topics:

•Understanding the default 802.1x configuration

•Enabling 802.1x authentication

•Configuring the switch-to-RADIUS-server comunication

•Enabling periodic reauthentication

•Changing the quiet period

•Changing the switch-to-client retransmission time

•Setting the switch-to-client frame-retransmission number

•Enabling multiple hosts

•Resetting the 802.1x configuration to default values

•Displaying 802.1x statistics and status

Configuring Spanning Tree Protocol

For information on how to configure Spanning Tree Protocol, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1047906

The document contains information on the following topics:

•Enabling spanning tree

•Configuring spanning tree port priority

•Configuring spanning tree port cost

•Configuring the bridge priority of a VLAN

•Configuring the Hello Time

•Configuring the forward-delay time for a VLAN

•Configuring the maximum aging time for a VLAN

•Disabling spanning tree

Configuring MAC Table Manipulation

For information on how to configure MAC table manipulation, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048223

The document contains information on the following topics:

•Enabling known MAC address traffic

•Creating a static entry in the MAC address table

•Configuring the aging timer

•Verifying the aging time

Port Security

The topic of enabling known MAC address traffic deals with port security. Port security can be either static or dynamic.

Static port security allows the user to specify which devices are allowed access through a given switch port. The specification is done manually by placing allowed device MAC addresses in the MAC address table. Static port security is also known as MAC address filtering.

Dynamic port security is similar. However, instead of specifying the MAC address of the devices, the user specifies the maximum number of devices that is allowed on the port. If the maximum number specified is more than the number of MAC addresses specified manually, the switch learns the MAC address automatically, up to the maximum specified. If the maximum number specified is less than the number of MAC addresess already specified statically, an error message is produced.

The following command is used to specify static or dynamic port security.

Command

Purpose

Router(config)# mac-address-table secure [mac-address | maximum maximum addresses] fastethernet interface-id [vlan vlan id]

mac-address enables static port security. The maximum keyword enables dynamic port security.

Configuring Cisco Discovery Protocol

For information on how to configure Cisco Discovery Protocol (CDP), see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048365

The document contains information on the following topics:

•Enabling CDP

•Enabling CDP on an interface

•Monitoring and maintaining CDP

Configuring the Switched Port Analyzer

For information on how to configure a switched port analyzer (SPAN) session, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048473

The document contains information on the following topics:

•Configuring the SPAN sources

•Configuring SPAN destinations

•Verifying SPAN sessions

•Removing sources or destinations from a SPAN session

Configuring Power Management on the Interface

For information on how to configure inline power for access points or Cisco IP phones, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048551

Configuring IP Multicast Layer 3 Switching

For information on how to configure IP multicast Layer 3 switching, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048610

The document contains information on the following topics:

•Enabling IP multicast routing globally

•Enabling IP protocol-independent multicast (PIM) on Layer 3 interfaces

•Verifying IP multicast Layer 3 hardware switching summary

•Verifying the IP multicast routing table

Configuring IGMP Snooping

For information on how to configure IGMP snooping, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1048777

The document contains information on the following topics:

•Enabling or disabling IGMP snooping

•Enabling IGMP immediate-leave processing

•Statically configuring an interface to join a group

•Configuring a multicast router port

IGMP Version 3

In support of the IGMPv3 feature in Cisco IOS Release 12.4(15)T, the groups and count keywords were added to the show ip igmp snooping command, and the output of the show ip igmp snooping command was modified to include global information about IGMP snooping groups. Use the show ip igmp snooping command with the groups keyword to display the multicast table learned by IGMP snooping for all VLANs, or the show ip igmp snooping command with the groups keyword, vlan-id keyword, and vlan-id argument to display the multicast table learned by IGMP snooping for a specific VLAN. Use the show ip igmp snooping command with the groups and count keywords to display the number of multicast groups learned by IGMP snooping.

Configuring Per-Port Storm Control

For information on how to configure per-port storm control, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1049009

The document contains information on the following topics:

•Enabling per-port storm-control

•Disabling per-port storm-control

Configuring Separate Voice and Data Subnets

For information on how to configure separate voice and data subnets, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1049866

Managing the Switch

For information on management of the switch, see:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/esw_cfg.html#wp1049978

The document contains information on the following topics:

•Adding Trap Managers

•Configuring IP Information

•Enabling Switch Port Analyzer

•Managing the ARP Table

•Managing the MAC Address Tables

•Removing Dynamic Addresses

•Adding Secure Addresses

•Configuring Static Addresses

•Clearing all MAC Address Tables