To enable an IPv4 or IPv6 address family under Enhanced Interior Gateway Routing Protocol (EIGRP), use the address-family command in the appropriate mode. To remove the address family from the EIGRP configuration, use the no form of this command.

Command Default

No default behavior or values

Command Modes

Router configuration

VRF configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the address-family ipv4 command to configure IPv4 address family sessions in EIGRP and the address-family ipv6 command to configure IPv6 address family sessions in EIGRP.

EIGRP Virtual Private Networks (VPNs) can be configured under IPv4 and IPv6 address family configuration modes after first entering VRF configuration mode. All commands in address family configuration mode can be configured in VRF address families except the autonomous-system and maximum-prefix commands.

Related Commands

To authenticate all EIGRP protocol traffic on one or more interfaces based on the MD5 algorithm, use the authentication keychain command in an appropriate configuration mode. To disable authentication, use the no form of this command.

Command Default

Authentication is disabled.

Command Modes

IPv4 address family interface configuration

IPv6 address family interface configuration

IPv4 VRF address family interface configuration

IPv6 VRF address family interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the address-family ipv4 command to configure IPv4 address family sessions in EIGRP and the address-family ipv6 command to configure IPv6 address family sessions in EIGRP.

EIGRP Virtual Private Networks (VPNs) can be configured under IPv4 and IPv6 address family configuration modes after first entering VRF configuration mode.

Related Commands

To allow automatic summarization of subnet routes into network-level routes for an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the auto-summary command in the appropriate configuration mode. To disable this function and send subprefix routing information across classful network boundaries, use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

The behavior of this command is disabled by default. (The software sends subnet routing information across classful network boundaries.)

Command Modes

IPv4 Address family configuration

IPv4 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Route summarization reduces the amount of routing information in the routing tables. Use the auto-summary command to allow the software to create summary subprefixes to the classful network boundary when crossing classful network boundaries.

EIGRP summary routes are given an administrative distance value of 5. You cannot configure this value.

Related Commands

To configure the autonomous-system number for an address-family of Enhanced Interior Gateway Routing Protocol (EIGRP) routing process, use the autonomous-system command in the address family configuration mode. To remove the autonomous-system number for an address-family of EIGRP routing process, use the no form of this command.

Command Default

None

Command Modes

IPv4 address family configuration (For EIGRP configured using virtual-name only).

IPv4 address family configuration (For EIGRP configured using virtual-name only).

IPv4 VRF address family configuration.

IPv6 VRF address family configuration.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the autonomous-system command in IPv4 or IPv6 VRF address family configuration mode.

The same VRF-autonomous-system combination cannot be used across multiple process instances.

Related Commands

To configure the percentage of bandwidth that may be used by EIGRP on an interface, use the bandwidth-percent command in interface configuration mode. To restore the default value, use the no form of this command.

Command Default

percent : 50

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

EIGRP uses up to 50 percent of the bandwidth of a link, as defined by the bandwidth interface configuration command. This command may be used if some other fraction of the bandwidth is desired. Values greater than 100 percent may be configured. The configuration option may be useful if the bandwidth is set artificially low for other reasons.

Related Commands

To remove and re-establish Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor entries from the appropriate table, use the clear eigrp neighbors command in EXEC configuration mode.

Command Default

When no autonomous system number or VRF instance is specified, all EIGRP neighbor entries are cleared from the table.

Command Modes

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Related Commands

To remove and relearn Enhanced Interior Gateway Routing Protocol (EIGRP) topology entries from the appropriate table, use the clear eigrp topology command in EXEC configuration mode.

Command Default

No EIGRP topology entries are cleared.

Command Modes

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Related Commands

To control the candidate default routing information for an Enhanced Interior Gateway Routing Protocol (EIGRP), use the defaultinformation command in the appropriate configuration mode. To suppress EIGRP candidate default information in incoming or outgoing updates, use the no form of this command.

Command Default

Default routing information is not accepted or flagged.

Command Modes

Address family configuration

IPv4 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

To set metrics for an Enhanced Interior Gateway Routing Protocol (EIGRP), use the defaultmetric command in the appropriate configuration mode. To remove the metric values and restore the default state, use the no form of this command.

Command Default

No default values

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the default-metric command to provide default metric values while redistributing a protocol into EIGRP.

Metric defaults have been carefully set to work for a wide variety of networks. Take great care when changing these values.

Related Commands

To allow the use of one of two administrative distances—internal and external—that could provide a better route to a node, use the distance command in the appropriate configuration mode. To reset these values to their defaults, use the no form of this command.

Command Default

internal-distance : 90

external-distance : 170

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

An administrative distance is a rating of the trustworthiness of a routing information source, such as an individual router or a group of routers. Numerically, an administrative distance is an integer from 0 to 255. In general, the higher the value, the lower the trust rating. An administrative distance of 255 means the routing information source cannot be trusted at all and should be ignored.

Use the distance command if another protocol is known to provide a better route to a node than was actually learned through the external Enhanced Interior Gateway Routing Protocol (EIGRP) or some internal routes should be preferred by EIGRP.

To display the default administrative distance for a specified routing process, use the show protocols EXEC command.

Related Commands

To configure the hello interval for an interface, use the hello-interval command in interface configuration mode. To restore the default value, use the no form of this command.

Command Default

For low-speed, nonbroadcast multiaccess (NBMA) networks: 60 seconds

For all other networks: 5 seconds

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

To configure the hold time for an interface, use the hold-time command in interface configuration mode. To restore the default value, use the no form of this command.

Command Default

Three times the default hello interval time of 15 seconds.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

On very congested and large networks, the default hold time might not be sufficient time for all routers to receive hello packets from their neighbors. In this case, you may want to increase the hold time.

We recommend that the hold time be at least three times the hello interval. If a router does not receive a hello packet within the specified hold time, routes through this router are considered unavailable.

Increasing the hold time delays route convergence across the network.

To ensure nonstop forwarding during RP failovers, we recommend that the hold time be increased to 30 seconds.

Related Commands

To define the interfaces on which the Enhanced Interior Gateway Routing Protocol (EIGRP) routing protocol runs, use the interface command in the appropriate configuration mode. To disable EIGRP routing for interfaces, use the no form of this command.

Command Default

When you do not specify this command in configuration mode, EIGRP routing for interfaces is not enabled.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the interface command to associate a specific interface with an EIGRP process. The interface remains associated with the process even when the IPv4 address of the interface changes.

This command places the router in interface configuration mode, from which you can configure interface-specific settings. Commands configured under this mode (such as the hello-interval command) are automatically bound to that interface.

To enable the logging of changes in Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor adjacencies, use the log-neighbor-changes command in the appropriate configuration mode. To disable the logging of changes in EIGRP neighbor adjacencies, use the no form of this command.

Command Default

This command has no keywords or arguments.

Adjacency changes are not logged.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the log-neighbor-changes command to log neighbor adjacency changes, monitor the stability of the routing system, and help detect problems. Logging is disabled by default. To disable the logging of neighbor adjacency changes, use the no form of this command.

To enable the logging of Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor warning messages, use the log-neighbor-warnings command in the appropriate configuration mode. To disable the logging of EIGRP neighbor warning messages, use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

Neighbor warning messages are not logged.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the log-neighbor-warnings command to disable and enable neighbor warning messages. When neighbor warning messages occur, they are not logged by default.

To control the maximum number of parallel routes that the Enhanced Interior Gateway Routing Protocol (EIGRP) can support, use the maximum-paths command in the appropriate configuration mode. To remove the maximum-paths command from the configuration file and restore the system to its default condition with respect to the routing protocol, use the no form of this command.

Command Default

maximum : 4

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the maximum-paths command to allow the EIGRP protocol to install multiple paths into the routing table for each prefix. Multiple paths are installed for both internal and external routes, providing these routes are learned in the same autonomous system and that they are equal cost (according to the EIGRP best path algorithm).

To limit the number of prefixes that are accepted under a VRF address family by Enhanced Interior Gateway Routing Protocol (EIGRP), use the maximum-prefix command in IPv4 VRF address family configuration mode. To disable this function, use the no form of this command.

Command Default

threshold: 75 percent

dampened : False

reset-time : 15 minutes

restart : 5 minutes

restart-count : 3

warning-only : False

Command Modes

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the maximum-prefix command to limit the number of prefixes that are accepted from all sources. When the maximum prefix limit is exceeded, sessions with remote peers are torn down, all routes learned from remote peers and through redistribution are removed from the topology and routing tables, and redistribution and peering are suspended for the default or user-defined time period.

Related Commands

To set metrics for an Enhanced Interior Gateway Routing Protocol (EIGRP) interface, use the metric command in interface configuration mode. To remove the metric values and restore the default state, use the no form of this command.

Command Default

Metric values are not set.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the metric command to provide metric values while redistributing a protocol into an EIGRP interface. Metric defaults have been carefully set to work for a wide variety of networks. Take great care when changing these values.

The picoseconds keyword is supported only in 64 bit mode.

Related Commands

To advertise as unreachable those Enhanced Interior Gateway Routing Protocol (EIGRP) routes with a hop count higher than is specified by the command, use the metric maximum-hops command in the appropriate configuration mode. To reset the value to the default, use the no form of this command.

Command Default

hops-number : 100

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the metric maximum-hops command to provide a safety mechanism that breaks any potential count-to-infinity problems. This command causes the EIGRP routing protocol to advertise as unreachable routes with a hop count greater than the value assigned to the hops-number argument.

Related Commands

To set a RIB scale for EIGRP, use the metric rib-scale command in an appropriate configuration mode. To remove the RIB scale and restore the default state, use the no form of this command.

Command Default

Default RIB scale is 128 in the 64 bit mode.

In 32 bit mode, rib scale is always 1.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration (Only supported in 64 bit mode)

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The ability to scale the RIB metric is provided through the use of the metric rib-scale configuration command. When entered, the command will result in all routes in the RIB being cleared and replaced with the new metric values.

To allow the tuning of the Enhanced Interior Gateway Routing Protocol (EIGRP) metric calculations, use the metric weights command in the appropriate configuration mode. To reset the values to their defaults, use the no form of this command.

Command Default

tos: 0

k1: 1

k2: 0

k3: 1

k4: 0

k5: 0

k6 0

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the metric weights command to alter the default behavior of EIGRP routing and metric computation and allow the tuning of the EIGRP metric calculation for a particular ToS.

If k5 equals 0, the composite EIGRP metric is computed according to the following formula:

metric = [k1 * bandwidth + (k2 * bandwidth)/(256 – load) + k3 * delay]

If k5 does not equal zero, an additional operation is performed:

metric = metric * [k5/(reliability + k4)]

Bandwidth is inverse minimum bandwidth of the path in BPS scaled by a factor of 2.56 * 1012. The range is from a 1200-bps line to 10 terabits per second.

Delay is in units of 10 microseconds. The range of delay is from 10 microseconds to 168 seconds. A delay of all 1s indicates that the network is unreachable.

The delay parameter is stored in a 32-bit field, in increments of 39.1 nanoseconds. The range of delay is from 1 (39.1 nanoseconds) to hexadecimal FFFFFFFF (decimal 4,294,967,040 nanoseconds). A delay of all 1s (that is, a delay of hexadecimal FFFFFFFF) indicates that the network is unreachable.

This table lists the default values used for several common media.

This command is supported only in 64 bit mode. The constraint k6 does not have effect in 64 bit mode.

Reliability is given as a fraction of 255. That is, 255 is a reliability of 100 percent or a perfectly stable link. Load is given as a fraction of 255. A load of 255 indicates a completely saturated link.

Related Commands

To define a neighboring router with which to exchange Enhanced Interior Gateway Routing Protocol (EIGRP) information, use the neighbor command in interface configuration mode. To remove an entry, use the no form of this command.

Command Default

No neighboring routers are defined.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the neighbor command to permit the point-to-point (nonbroadcast) exchange of routing information.

If a neighbor is configured on an interface using the neighbor command, the interface stops sending or receiving multicast hello messages. However, the interface can send or receive unicast hello messages. So each neighbor on a LAN must be configured individually .Multiple neighbor commands can be used to specify additional neighbors or peers.

Related Commands

To limit the number of prefixes that are accepted from a single Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor or all EIGRP VPN neighbors, use the neighbor maximum-prefix command in IPv4 VRF address family configuration mode. To disable this function, use the no form of this command.

Command Default

threshold: 75 percent

dampened : disabled

warning-only : disabled

reset-time : 15 minutes

restart : 5 minutes

restart-count : 3

Command Modes

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The neighbor maximum-prefixcommand is configured to protect an individual peering session or all peering sessions. When this feature is enabled and the maximum prefix limit is exceeded, the router tears down the peering session, clears all routes that are learned from the peer, and then places the peer in a penalty state for the default or user-defined time period. After the penalty time period expires, normal peering is reestablished.

Note	In EIGRP, neighbor commands have been used traditionally to configure static neighbors. In the context of this feature, however, the neighbor maximum-prefix command can be used to configure the maximum prefix limit for both statically configured and dynamically discovered neighbors.

When configuring the neighbor maximum-prefix command to protect a single peering session, just the maximum prefix limit, percentage threshold, and warning only configuration options can be configured. Session dampening, restart, and reset timers are configured on a global basis.

Related Commands

To instruct the Enhanced Interior Gateway Routing Protocol (EIGRP) process to use the received next-hop value when advertising the routes, use the next-hop-self disablecommand in interface configuration mode. To revert to the default, use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

EIGRP always sets the IP next-hop value to be itself.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

EIGRP, by default, sets the IP next-hop value to be itself for routes that it is advertising, even when advertising those routes on the same interface from which learned them. To change this default, you must use the next-hop-self disable interface configuration command to instruct EIGRP to use the received next-hop value when advertising these routes.

The next-hop-self disable feature is not available for redistributed routes.

To disable Enhanced Interior Gateway Routing Protocol (EIGRP) nonstop forwarding (NSF), use the nsf disable command in appropriate configuration mode. To re-enable the EIGRP NSF from a disabled state, use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

NSF in EIGRP is enabled.

Command Modes

Router Configration

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If NSF is disabled, EIGRP will not be able to retain the routes learnt from its peers and may result in traffic loss during ISSU.

Related Commands

To disable sending and receiving "hello" messages on an Enhanced Interior Gateway Routing Protocol (EIGRP) interface and to disable formation of neighbors on the interface, use the passive-interface command in interface configuration mode. To reenable sending and receiving "hello messages", use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

passive-interface command is disabled on an interface.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the passive-interface command to disable sending of "hello" massages. The particular subnet on that interface will continue to be advertised by EIGRP to neighbors on other interfaces.

To inject routes from one routing domain into the Enhanced Interior Gateway Routing Protocol (EIGRP), use the redistribute command in the appropriate configuration mode. To remove the redistribute command from the configuration file and restore the system to its default condition in which the software does not redistribute routes, use the no form of this command.

Command Default

Route redistribution is disabled.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Redistributed routing information should always be filtered by the route- policy name keyword and argument. This filtering ensures that only those routes intended by the administrator are redistributed by EIGRP.

A default metric is usually required to redistribute routes from another protocol into EIGRP. The metric is configured through the default-metric command or under the route policy configured with the redistribute command. The two exceptions to this requirement are when EIGRP redistributes BGP routes on a provider edge (PE) router in an MPLS-VPN scenario and when EIGRP redistributes EIGRP routes from another autonomous-system number. In case of MPLS-VPN scenario, if the originating protocol of the route is EIGRP with the same autonomous-system, the metric would be learned automatically from the extended communities of the BGP route. In case of redistribution from EIGRP belonging to different autonomous-system, the metric would be learned automatically from the extended communities from RIB.

For information about routing policies, see the Routing Policy Commands on Cisco IOS XR Softwaremodule of the Cisco IOS XR Routing Command Reference.

Related Commands

To limit the number of prefixes redistributed into an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the redistribute maximum-prefix command in IPv4 VRF address family configuration mode. To disable this function, use the no form of this command.

Command Default

threshold: 75 percent

warning-only : disabled

reset-time : 15 minutes

restart : 5 minutes

restart-count : 3

dampened: disabled

Command Modes

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the redistribute maximum-prefix command to configure limit prefixes learned through redistribution. When the maximum prefix limit is exceeded, all routes learned from the Routing Information Base (RIB) are discarded and redistribution is suspended for the default or user-defined time period. The maximum prefix limit that can be configured for redistributed prefixes is limited only by the available system resources on the router.

Related Commands

To apply a routing policy to updates advertised to or received from an Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor, use the route-policy command in the appropriate configuration mode. To disable applying routing policy to updates, use the no form of this command.

Command Default

No policy is applied.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the route-policy command to specify a routing policy for an inbound or outbound route. The policy can be used to filter routes or modify route attributes.

To configure a routing process and enter router configuration mode for Enhanced Interior Gateway Routing Protocol (EIGRP), use the router eigrp command in global configuration mode. To turn off the EIGRP routing process, use the no form of this command.

Command Default

No routing process is defined.

Command Modes

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

• An explicit autonomous-system configuration is required for the default/global VRF when EIGRP is configured using virtual instance-name.

• Up to 4 EIGRP instances can be configured.

To configure a router ID for an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the router-id command in the appropriate configuration mode. To cause the software to use the default method of determining the router ID, use the no form of this command.

Command Default

If this command is not configured, EIGRP chooses an IPv4 address as the router ID from one of its interfaces.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

It is good practice to use the router-id command to explicitly specify a unique 32-bit numeric value for the router ID. This action ensures that EIGRP can function regardless of the interface address configuration.

To display prefix accounting information for Enhanced Interior Gateway Routing Protocol (EIGRP) processes, use the show eigrp accounting command in EXEC mode.

Command Default

This command has no arguments or keywords.

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

To display information about interfaces configured for Enhanced Interior Gateway Routing Protocol (EIGRP), use the show eigrp interfaces command in EXEC mode.

Command Default

This command has no arguments or keywords.

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the show eigrp interfaces command to determine on which interfaces EIGRP is active and learn information about EIGRP related to those interfaces.

If an interface is specified, only that interface is displayed. Otherwise, all interfaces on which EIGRP is running are displayed.

If an autonomous system is specified, only the routing process for the specified autonomous system is displayed. Otherwise, all EIGRP processes are displayed.

Related Commands

To display information about neighbors discovered by Enhanced Interior Gateway Routing Protocol (EIGRP), use the show eigrp neighbors command in EXEC mode.

Command Default

No default behavior or values

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the show eigrp neighbors command to determine when neighbors become active and inactive. This command is also useful for debugging certain types of transport problems.

To display the Enhanced Interior Gateway Routing Protocol (EIGRP) topology table, use the show eigrp topology command in EXEC mode.

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

When the show eigrp topology command is used without any keywords or arguments, only routes that are feasible successors are displayed.

The show eigrp topology command can be used to determine Diffusing Update Algorithm (DUAL) states and to debug possible DUAL problems.

To display the number of Enhanced Interior Gateway Routing Protocol (EIGRP) packets sent and received, use the show eigrp traffic command in EXEC mode.

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the show eigrp traffic command to find the number of packets sent and received.

In addition, this command is useful in determining whether packets from one node are not reaching the neighboring node due to connectivity or configuration problems.

To display information about the Enhanced Interior Gateway Routing Protocol (EIGRP) process configuration, use the show protocols command in EXEC mode.

Command Modes

EXEC

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the show protocols command to get information about the protocols running on the router and to quickly determine which protocols are active. The command is designed to summarize the important characteristics of the running protocol, and command output varies depending on the specific protocol selected.

For EIGRP, the command output lists the instance number, default AS context, router ID, default networks, distance, maximum paths, and so on.

To configure the Site of Origin (SoO) filtering on an Enhanced Interior Gateway Routing Protocol (EIGRP) interface, use the site-of-origin command in interface configuration mode. To disable SoO filtering on an interface, use the no form of this command.

Command Default

No default behavior or values

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

An EIGRP process must be capable of retrieving the SoO attribute on routes redistributed from the Border Gateway Protocol (BGP) when required to support complex topologies that include MPLS VPN links between sites with backdoor links.

Use the site-of-origin command to set an SoO BGP extended community attribute that is used to identify routes that have originated from a site so that the readvertisement of that prefix back to the source site can be prevented. The SoO extended community uniquely identifies the site from which a provider edge (PE) router has learned a route.

To disable split horizon for an Enhanced Interior Gateway Routing Protocol (EIGRP) process, use the split-horizon disable command in interface configuration mode. To enable split horizon, use the no form of this command.

Syntax Description

This command has no keywords or arguments.

Command Default

Split horizon is enabled for an EIGRP process.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

To configure a router as a stub for Enhanced Interior Gateway Routing Protocol (EIGRP), use the stub command in the appropriate configuration mode. To disable this function, use the no form of this command.

Command Default

Stub routing is disabled.

When stub routing is specified, connected and summary routes are advertised by default.

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the stub command to configure a router as a stub in which the router directs all IP traffic to a distribution router.

The stub command can be modified with several options, and these options can be used in any combination except for the receive-only keyword.

The receive-only keyword restricts the router from sharing any of its routes with any other router in that EIGRP autonomous system and does not permit any other option to be specified because it prevents any type of route from being sent. The four other optional keywords ( connected , static , summary , and redistributed ) can be used in any combination but cannot be used with the receive-only keyword. If any of these four keywords is used with the stub command, only the route types specified by the particular keyword or keywords are sent. Route types specified by the nonused keyword or keywords are not sent.

The connected keyword permits EIGRP stub routing to send connected routes. If all the connected routes are not covered by EIGRP interfaces, it may be necessary to redistribute connected routes with the redistribute connected command under the EIGRP process. This option is enabled by default.

The static keyword permits EIGRP stub routing to send static routes. Without the configuration of this option, EIGRP does not send any static routes. You may still need to redistribute static routes with the redistribute static command.

The summary keyword permits EIGRP stub routing to send summary routes. Summary routes can be created manually with the summary address command or automatically at a major network border router with the auto-summary command enabled. This option is enabled by default.

The redistributed keyword permits EIGRP stub routing to send other routing protocols and autonomous systems. Without the configuration of this option, EIGRP does not advertise redistributed routes.

Related Commands

To configure a summary aggregate address for the specified Enhanced Interior Gateway Routing Protocol (EIGRP) interface, use the summary-address command in interface configuration mode. To disable a configuration, use the no form of this command.

Command Default

An administrative distance of 5 is applied to EIGRP summary routes.

No summary addresses are predefined.

Command Modes

Interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The summary-address command is used to configure interface-level address summarization. EIGRP summary routes are given an administrative distance of 5. The administrative distance is used to advertise a summary without installing it in the routing table.

By default, EIGRP summarizes subnet routes to the network level. The no auto-summary command can be entered to configure subnet level summarization.

Related Commands

To adjust the Enhanced Interior Gateway Routing Protocol (EIGRP) routing wait time, use the timers active-time command in the appropriate configuration mode. To disable this function, use the timers active-time no form of the command.

Command Default

Disabled

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the timers active-time command to control the time the router waits (after query is sent) before declaring the route to be in the stuck in active (SIA) state.

To set the timer that determines how long an NSF-aware Enhanced Interior Gateway Routing Protocol (EIGRP) router holds routes for an inactive peer, use the timers nsf route-hold command in the appropriate configuration mode. To return the route hold timer to the default value, use the no form of this command.

Command Default

EIGRP NSF awareness is enabled.

seconds :480

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the timers nsf route-hold command to set the maximum period of time that the NSF-aware router holds known routes for an NSF-capable neighbor during a switchover operation or a well-known failure condition. The route hold timer is configurable so that you can tune network performance and avoid undesired effects, such as packet loss on routes if the switchover operation takes too much time. When this timer expires, the NSF-aware router scans the topology table and discards any stale routes, allowing EIGRP peers to find alternate routes instead of waiting during a long switchover operation.

To control load balancing in an Enhanced Interior Gateway Routing Protocol (EIGRP)-based internetwork, use the variance command in the appropriate configuration mode. To reset the variance to the default value, use the no form of this command.

Command Default

multiplier : 1 (equal-cost load balancing)

Command Modes

IPv4 address family configuration

IPv6 address family configuration

IPv4 VRF address family configuration

IPv6 VRF address family configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the variance command to set a variance on the EIGRP router so that the router can determine the feasibility of a potential route. A route is feasible if the next router in the path is closer to the destination than the current router and the metric for the entire path is within the variance. Only paths that are feasible can be used for load balancing and included in the routing table.

If the following two conditions are met, the route is considered feasible and can be added to the routing table:

1. The local best metric must be greater than the metric learned from the next router.

2. The multiplier times the local best metric for the destination must be greater than or equal to the metric through the next router.

To define a VPN routing and forwarding (VRF) instance and enter VRF configuration mode, use the vrf command in router configuration mode. To remove a VRF instance, use the no form of this command.

Command Default

No VRFs are defined.

Command Modes

Router configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the vrf command to configure a VRF instance. A VRF instance is a collection of VPN routing and forwarding tables maintained at the provider edge (PE) router.

From VRF configuration mode, you must enter address family configuration mode and then issue commands, such as the auto-summary command.

A single EIGRP routing process can support multiple VRFs. The number of VRFs that can be configured is limited by available system resources on the router, which is determined by the number of VRFs, running processes, and available memory. However, only a single VRF can be supported by each VPN. Redistribution between different VRFs is not supported.

MPLS VPN support between PE and customer edge (CE) routers is configured only on PE routers that provide VPN services over the service provider backbone. The customer site does not require any changes to equipment or configurations to support the EIGRP VPN. Typically, a metric must be configured for routes to be advertised to the CE router. The metric can be configured under the route-policy for the redistribute protocol command or configured with the default-metric command.

You must remove IPv4/IPv6 addresses from an interface prior to assigning, removing, or changing a VRF on an IP interface. If this is not done in advance, any attempt to change the VRF on an IP interface is rejected.

Related Commands