EIGRP Support for MTR

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You must enable IP routing on the router for MTR to operate. MTR supports static and dynamic routing in Cisco IOS software. You can enable dynamic routing per-topology to support inter-domain and intra-domain routing. Route calculation and forwarding are independent for each topology. MTR support is integrated into Cisco IOS software for the following protocols:

• Border Gateway Protocol (BGP)
• Enhanced Interior Gateway Routing Protocol (EIGRP)
• Integrated Intermediate System-to-Intermediate System (IS-IS)
• Open Shortest Path First (OSPF)

You apply the per-topology configuration in router address family configuration mode of the global routing process (router configuration mode). The address family and subaddress family are specified when entering address-family configuration mode. You specify the topology name and topology ID by entering the topology command in address-family configuration mode.

You configure each topology with a unique topology ID under the routing protocol. The topology ID is used to identify and group NLRI for each topology in updates for a given protocol. In OSPF, EIGRP, and IS-IS, you enter the topology ID during the first configuration of the topology command for a class-specific topology. In BGP, you configure the topology ID by entering the bgp tid command under the topology configuration.

You can configure class-specific topologies with different metrics than the base topology. Interface metrics configured on the base topology can be inherited by the class-specific topology. Inheritance occurs if no explicit inheritance metric is configured in the class-specific topology.

You configure BGP support only in router configuration mode. You configure Interior Gateway Protocol (IGP) support in router configuration mode and in interface configuration mode.

By default, interfaces are not included in non-base topologies. For routing protocol support for EIGRP, IS-IS, and OSPF, you must explicitly configure a non-base topology on an interface. You can override the default behavior by using the all-interfaces command in address family topology configuration mode. The all-interfaces command causes the non-base topology to be configured on all interfaces of the router that are part of the default address space or the VRF in which the topology is configured.

The configuration of a Multitopology Routing (MTR) topology in interface configuration mode allows you to enable or disable MTR on a per-interface basis. By default, a class-specific topology does not include any interfaces.

You can include or exclude individual interfaces by configuring the topology interface configuration command. You specify the address family and the topology (base or class-specific) when entering this command. The subaddress family can be specified. If no subaddress family is specified, the unicast subaddress family is used by default.

You can include globally all interfaces on a device in a topology by entering the all-interfaces command in routing topology configuration mode. Per-interface topology configuration applied with the topology command overrides global interface configuration.

The interface configuration support for MTR has these characteristics:

• Per-interface routing configuration: Interior Gateway Protocol (IGP) routing and metric configurations can be applied in interface topology configuration mode. Per-interface metrics and routing behaviors can be configured for each IGP.
• Open Shortest Path First (OSPF) interface topology configuration: Interface mode OSPF configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure an interface cost or disable OSPF routing without removing the interface from the global topology configuration.
• Enhanced Interior Gateway Routing Protocol (EIGRP) interface topology configuration: Interface mode EIGRP configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure various EIGRP features.
• Intermediate System-to-Intermediate System (IS-IS) interface topology configuration: Interface mode IS-IS configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure an interface cost or disable IS-IS routing without removing the interface from the global topology configuration.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    router eigrp name

4.    address-family ipv4 [unicast | multicast | vrf vrf-name ] autonomous-system as-number

5.    topology {base | topology-name tid number}

6.    end

7.    show ip protocols topology name [summary]

8.    show ip eigrp topology name

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	router eigrp name Example: Router(config)# router eigrp MTR	Configures an EIGRP process for MTR, and enters router configuration mode. You can use the command without configuring MTR, but it defaults to the base topology.
Step 4	address-family ipv4 [unicast | multicast | vrf vrf-name ] autonomous-system as-number Example: Router(config-router)# address-family ipv4 autonomous-system 1	Enters router address family configuration mode to configure EIGRP for MTR.
Step 5	topology {base | topology-name tid number} Example: Router(config-router-af)# topology VIDEO tid 100	Configures an EIGRP process to route IP traffic under the specified topology instance and enters router address family topology configuration mode. Each topology must be configured with a unique topology ID. The topology ID must be entered each time this command is entered.
Step 6	end Example: Router(config-router-af-topology)# end	Exits router address family configuration mode and returns to privileged EXEC mode.
Step 7	show ip protocols topology name [summary] Example: Router# show ip protocols topology VIDEO	Displays the status of routing protocols configured in a topology. Tip    This command can be entered to display the status, under a topology, of any configured routing protocol.
Step 8	show ip eigrp topology name Example: Router# show ip eigrp topology VIDEO	Displays the routing table of an EIGRP process configured under a topology.

• What to Do Next

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface type number

4.    topology ipv4 [multicast | unicast] {topology-name [disable] | base}

5.    eigrp as-number delay value

6.    eigrp as-number next-hop-self

7.    eigrp as-number shutdown

8.    eigrp as-number split-horizon

9.    eigrp as-number summary-address ip-address wildcard-mask [distance]

10.    end

11.    show ip eigrp topology name interfaces

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface type number Example: Router(config)# interface Ethernet 0/0	Specifies the interface type and number, and enters interface configuration mode.
Step 4	topology ipv4 [multicast | unicast] {topology-name [disable] | base} Example: Router(config-if)# topology ipv4 VOICE	Configures an MTR topology instance on an interface and enters interface topology configuration mode. Note    Entering this command with the disable keyword disables the topology instance on the interface. This form is used to exclude a topology configuration from an interface.
Step 5	eigrp as-number delay value Example: Router(config-if-topology)# eigrp 1 delay 100000	Configures the delay value that EIGRP uses for interface metric calculation. The value argument is entered in microseconds. The example configures an interface delay metric of 100 milliseconds.
Step 6	eigrp as-number next-hop-self Example: Router(config-if-topology)# eigrp 1 next-hop-self	Configures an EIGRP process to advertise itself as the next hop. This command is enabled by default.
Step 7	eigrp as-number shutdown Example: Router(config-if-topology)# eigrp 1 shutdown	Disables an EIGRP process on the interface without disabling the global topology configuration on the interface.
Step 8	eigrp as-number split-horizon Example: Router(config-if-topology)# eigrp 1 split-horizon	Configures an EIGRP process to use split horizon. This command is enabled by default.
Step 9	eigrp as-number summary-address ip-address wildcard-mask [distance] Example: Router(config-if-topology)# eigrp 1 summary-address 10.1.1.0 0.0.0.255	Configures an EIGRP summary address. An administrative distance of 5 is applied to EIGRP summary routes if the distance is not specified.
Step 10	end Example: Router(config-if-topology)# end	Exits interface topology configuration mode and returns to privileged EXEC mode.
Step 11	show ip eigrp topology name interfaces Example: Router# show ip eigrp topology VOICE interfaces	Displays information about interfaces, on which EIGRP is configured, in a topology.

SUMMARY STEPS

1.    enable

2.    show ip interface [type number] [topology {name | all | base}] [stats]

3.    show ip traffic [topology {name | all | base}]

4.    clear ip interface type number [topology {name | all | base}] [stats]

5.    clear ip traffic [topology {name | all | base}]

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Device> enable	Enables privileged EXEC mode. Enter your password if prompted.
Step 2	show ip interface [type number] [topology {name | all | base}] [stats] Example: Device# show ip interface FastEthernet 1/10 stats	(Optional) Displays IP traffic statistics for all interfaces or statistics related to the specified interface. If you specify an interface type and number, information for that specific interface is displayed. If you specify no optional arguments, information for all the interfaces is displayed. If the topology name keyword and argument are used, statistics are limited to the IP traffic for that specific topology. The base keyword displays the IPv4 unicast base topology.
Step 3	show ip traffic [topology {name | all | base}] Example: Device# show ip traffic topology VOICE	(Optional) Displays global IP traffic statistics (an aggregation of all the topologies when MTR is enabled) or statistics related to a particular topology. The base keyword is reserved for the IPv4 unicast base topology.
Step 4	clear ip interface type number [topology {name | all | base}] [stats] Example: Device# clear ip interface FastEthernet 1/10 topology all	(Optional) Resets interface-level IP traffic statistics. If the topology keyword and a related keyword are not used, only the interface-level aggregate statistics are reset. If all topologies need to be reset, use the all keyword as the topology name.
Step 5	clear ip traffic [topology {name | all | base}] Example: Device# clear ip traffic topology all	(Optional) Resets IP traffic statistics. If no topology name is specified, global statistics are cleared.