-
Cisco IOS IP Routing Protocols Command Reference
-
Introduction
-
BGP Commands: A through B
-
BGP Commands: C through I
-
BGP Commands: M through neighbor soo
-
BGP Commands: neighbor timers through show bgp nsap summary
-
BGP Commands: show ip bgp through T
-
EIGRP Commands: A through I
-
EIGRP Commands: M through V
-
Integrated IS-IS Commands: A through I
-
Integrated IS-IS Commands: L through V
-
On-Demand Routing Commands
-
OSPF Commands: A through ip ospf demand-circuit
-
OSPF Commands: ip ospf flood-reduction through R
-
OSPF Commands: show ip ospf through T
-
IP Routing Protocol-Independent Commands: A through R
-
IP Routing Protocol-Independent Commands: S through T
-
RIP Commands
-
Table Of Contents
ip authentication key-chain eigrp
EIGRP Commands
address-family ipv4 (EIGRP)
To enter IPv4 address family configuration mode to configure an Enhanced Interior Gateway Routing Protocol (EIGRP) Virtual Private Network (VPN), use the address-family ipv4 command in address family configuration mode. To remove the address family from the EIGRP configuration, use the no form of this command.
address-family ipv4 [unicast] [vrf vrf-name]
no address-family ipv4 [unicast] [vrf vrf-name]
Syntax Description
unicast
(Optional) Specifies the unicast address family.
vrf vrf-name
(Optional) Specifies the name of the VRF.
Command Default
A default VRF is automatically created when this command is entered without the vrf keyword.
Command Modes
Address family configuration
Command History
Usage Guidelines
The address-family ipv4 command is used to configure IPv4 address family sessions under EIGRP. To leave address family configuration mode without removing the address family configuration, use the exit-address-family command.
EIGRP VPNs can be configured only under IPv4 address family configuration mode. A virtual routing and forwarding instance (VRF) and route distinguisher must be defined before the address family session can be created.
A single EIGRP routing process can support multiple VRFs. The number of VRFs that can be configured is limited only 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, and redistribution between different VRFs is not supported.
MPLS VPN support between PE and 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. A metric must be configured for routes to be advertised to the CE router. The metric can be configured using the redistribute (IP) command or configured with the default-metric (EIGRP) command.
Examples
The following example, starting in global configuration mode, configures an IPv4 address family session for the VRF named RED:
Router(config)# ip vrf REDRouter(config-vrf)# rd 1:1Router(config-vrf)# exitRouter(config)# router eigrp 1Router(config-router)# address-family ipv4 vrf REDRouter(config-router-af)# autonomous-system 101Router(config-router-af)# network 172.16.0.0Router(config-router-af)# default-metric 10000 100 255 1 1500Router(config-router-af)# exit-address-familyRelated Commands
autonomous-system (EIGRP)
To configure an Enhanced Interior Gateway Routing Protocol (EIGRP) routing process to run within a VPN routing and forwarding (VRF) instance, use the autonomous-system command in address family configuration mode. To remove an EIGRP routing process from within a VPN VRF instance, use the no form of this command.
autonomous-system autonomous-system-number
no autonomous-system autonomous-system-number
Syntax Description
Command Default
An EIGRP routing process does not run within a VRF.
Command Modes
Address family configuration
Command History
Usage Guidelines
This command can only be configured if a VRF name is specified when entering address family configuration mode.
Examples
The following example shows how to configure an EIGRP routing process within a VRF:
router eigrp 65200address-family ipv4 vrf VRF2autonomous-system 65500Related Commands
auto-summary (EIGRP)
To allow automatic summarization of subnet routes into network-level routes, use the auto-summary command in router configuration mode. To disable this function and send subprefix routing information across classful network boundaries, use the no form of this command.
auto-summary
no auto-summary
Syntax Description
This command has no arguments or keywords.
Command Default
The behavior of this command is disabled by default (the software sends subprefix routing information across classful network boundaries).
Command Modes
Router configuration
Command History
Usage Guidelines
Route summarization reduces the amount of routing information in the routing tables. By default, Border Gateway Protocol (BGP) does not accept subnets redistributed from an Interior Gateway Protocol (IGP). To allow the software to create summary subprefixes to the classful network boundary when crossing classful network boundaries, use the auto-summary command.
To advertise and carry subnet routes in BGP, use an explicit network command because automatic summarization is disabled by default. If you have not entered a network command, you will not advertise network routes for networks with subnet routes unless they contain a summary route.
Enhanced Interior Gateway Routing Protocol (EIGRP) summary routes are given an administrative distance value of 5. You cannot configure this value.
Routing Information Protocol (RIP) Version 1 always uses automatic summarization. If you are using RIP Version 2, you can turn off automatic summarization by specifying the no auto-summary command. Disable automatic summarization if you must perform routing between disconnected subnets. When automatic summarization is off, subnets are advertised.
Examples
The following example enables automatic summarization for EIGRP process 109:
router eigrp 109auto-summaryRelated Commands
ip summary-address eigrp
Configures a summary aggregate address for a specified interface.
clear ip eigrp neighbors
To delete entries from the Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor table, use the clear ip eigrp neighbors command in privileged EXEC mode.
clear ip eigrp neighbors [ip-address | interface-type interface-number]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Specifying the interface-type and interface-number arguments removes the specified interface from the neighbor table that all entries learned via this interface.
Examples
The following example removes the neighbor whose address is 172.16.8.3:
Router# clear ip eigrp neighbors 172.16.8.3Related Commands
show ip eigrp interfaces
Displays information about interfaces configured for EIGRP.
clear ip eigrp vrf neighbor
To clear neighbor entries of the specified Enhanced Interior Gateway Routing Protocol (EIGRP) virtual routing and forwarding instance (VRF) from the Routing Information Base (RIB), use the clear ip eigrp vrf command in privileged EXEC mode.
clear ip eigrp vrf vrf-name autonomous-system-number neighbor [interface-number]
Syntax Description
Command Modes
Privileged EXEC
Command History
Examples
The following example shows how to clear EIGRP neighbors reached through the VRF named RED in autonomous system 45000:
Router# clear ip eigrp vrf RED 45000 neighborThe following example shows how to clear EIGRP neighbors reached through the VRF named GREEN in autonomous-system 101 learned through Ethernet interface 0/0:
Router# clear ip eigrp vrf GREEN 45000 neighbor ethernet 0/0Related Commands
default-information
To accept exterior or default routing information into Enhanced Interior Gateway Routing Protocol (EIGRP) processes, use the default-information command in router configuration mode. To suppress exterior or default routing information in incoming or outbound updates, use the no default-information in command.
default-information {allowed {in | out} | in | out} [acl-number | acl-name]
no default-information {allowed {in | out} | in | out}
Syntax Description
Command Default
Normally, exterior routes are always accepted and default information is passed between EIGRP processes when redistribution occurs.
Command Modes
Router configuration
Command History
Usage Guidelines
The default network of 0.0.0.0 used by Routing Information Protocol (RIP) can be redistributed by EIGRP.
Examples
The following example allows exterior or default routes to be received by the EIGRP process in autonomous system 23:
router eigrp 23default-information indefault-metric (EIGRP)
To set metrics for the Enhanced Interior Gateway Routing Protocol (EIGRP), use the default-metric command in router configuration mode. To remove the metric value and restore the default state, use the no form of this command.
default-metric bandwidth delay reliability loading mtu
no default-metric bandwidth delay reliability loading mtu
Syntax Description
Command Default
Only connected routes can be redistributed without a default metric. The metric of redistributed connected routes is set to 0.
Command Modes
Router configuration
Command History
Usage Guidelines
You must use a default metric to redistribute a protocol into EIGRP, unless you use the redistribute command. Automatic metric translations occur between IGRP and EIGRP. You do not need default metrics to redistribute IGRP or EIGRP into itself.
Note
The default-metric command does not affect EIGRP-to-EIGRP or IGRP-to-EIGRP distribution. To configure EIGRP-to-EIGRP or IGRP-to-EIGRP distribution, use route maps.
Metric defaults have been carefully set to work for a wide variety of networks. Take great care when changing these values.
Default metrics are supported only when you are redistributing from IGRP, EIGRP, or static routes.
Examples
The following example shows how the redistributed Routing Information Protocol (RIP) metrics are translated into EIGRP metrics with values as follows: bandwidth = 1000, delay = 100, reliability = 250, loading = 100, and MTU = 1500:
router eigrp 109network 172.16.0.0redistribute ripdefault-metric 1000 100 250 100 1500Related Commands
distance eigrp
To allow the use of two administrative distances—internal and external—that could be a better route to a node, use the distance eigrp command in router configuration mode. To reset these values to their defaults, use the no form of this command.
distance eigrp internal-distance external-distance
no distance eigrp
Syntax Description
Command Default
internal-distance: 90
external-distance: 170Command Modes
Router configuration
Command History
Usage Guidelines
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 eigrp command if another protocol is known to be able to provide a better route to a node than was actually learned via external EIGRP, or if some internal routes should really be preferred by EIGRP.
Table 65 lists the default administrative distances.
To display the default administrative distance for a specified routing process, use the show ip protocols command.
Examples
In the following example, the router eigrp global configuration command sets up EIGRP routing in autonomous system number 109. The network router configuration commands specify EIGRP routing on networks 192.168.7.0 and 172.16.0.0. The distance eigrp command sets the administrative distance of all EIGRP internal routes to 80 and all EIGRP external routes to 130.
router eigrp 109network 192.168.7.0network 172.16.0.0distance eigrp 80 130Related Commands
show ip protocols
Displays the parameters and current state of the active routing protocol process.
eigrp event-log-size
To set the size of the Enhanced Interior Gateway Routing Protocol (EIGRP) event log, use the eigrp event-log-size command in router configuration mode. To reset the size of the EIGRP event log to its default value, use the no form of this command.
eigrp event-log-size size
no eigrp event-log-size
Syntax Description
Command Default
This command is enabled.
Command Modes
Router configuration (config-router)
Command History
Usage Guidelines
When the configured size (number of lines) of the event log is exceeded, the last configured number of lines is retained, and the log becomes a rolling number of events with the most recent at the top of the log.
Examples
The following example shows how to set the size of the EIGRP event log to 5000010:
Router# configure terminalRouter(config)# router eigrp 2Router (config-router)# eigrp event-log-size 5000010Router (config-router)#Related Commands
eigrp interface
To set a threshold value to minimize hysteresis in a router-to-radio configuration, use the eigrp interface command in interface configuration mode. To reset the hysteresis threshold to the default value, use the no form of this command.
eigrp vmi-interface-number interface [dampening-change value] [dampening-interval value]
no eigrp vmi-interface-number interface [dampening-change value] [dampening-interval value]
Syntax Description
Defaults
Default for change-based dampening is 50 percent of the computed metric.
Default for interval-based dampening is 30 seconds.
Command Modes
Interface configuration
Command History
12.4(15)XF
This command was introduced.
12.4(15)T
This command was integrated into Cisco IOS Release 12.4(15)T.
Usage Guidelines
This command advertises routing changes for EIGRP traffic only.
The REPLY sent to any QUERY will always contain the latest metric information. Exceptions which will result in immediate UPDATE being sent:
•
•
•
Change-based Dampening
The default value for the change tolerance will be 50% of the computed metric. It can be configured in the range from 0 to 100 percent. If the metric change of the interface is not greater (or less) than the current metric plus or minus the specified amount, the change will not result in a routing change, and no update will be sent to other adjacencies.
Interval-based Dampening
The default value for the update intervals is 30 seconds. It can be configured in the range from 0 to 64535 seconds. If this option is specified, changes in routes learned though this interface, or in the interface metrics, will not be advertised to adjacencies until the specified interval is met. When the timer expires, any changes detected in any routes learned through the interface, or the metric reported by the interfaces will be sent out.
Examples
Change-based Dampening Example
The following example sets the threshold to 50 percent tolerance routing updates involving VMI interfaces and peers:
interface vmi1ip address 10.2.2.1 255.255.255.0ipv6 address 2001:0DB1:2::1/96ipv6 enableeigrp 1 interface dampening-change 50physical-interface Ethernet0/0Interval-based Dampening Example
The following example sets the interval to 30 seconds at which updates occur for topology changes that affect VMI interfaces and peers:
interface vmi1ip address 10.2.2.1 255.255.255.0ipv6 address 2001:0DB1:2::1/96ipv6 enableeigrp 1 interface dampening-interval 30physical-interface Ethernet0/0Related Commands
eigrp log-neighbor-changes
To enable the logging of changes in Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor adjacencies, use the eigrp log-neighbor-changes command in router configuration mode. To disable the logging of changes in EIGRP neighbor adjacencies, use the no form of this command.
eigrp log-neighbor-changes
no eigrp log-neighbor-changes
Syntax Description
This command has no arguments or keywords.
Command Default
Adjacency changes are logged.
Command Modes
Router configuration
Command History
Usage Guidelines
This command enables the logging of neighbor adjacency changes to monitor the stability of the routing system and to help detect problems. Logging is enabled by default. To disable the logging of neighbor adjacency changes, use the no form of this command.
Examples
The following configuration disables logging of neighbor changes for EIGRP process 209:
router eigrp 209no eigrp log-neighbor-changesThe following configuration enables logging of neighbor changes for EIGRP process 209:
router eigrp 209eigrp log-neighbor-changeseigrp log-neighbor-warnings
To enable the logging of Enhanced Interior Gateway Routing Protocol (EIGRP) neighbor warning messages, use the eigrp log-neighbor-warnings command in router configuration mode. To disable the logging of EIGRP neighbor warning messages, use the no form of this command.
eigrp log-neighbor-warnings [seconds]
no eigrp log-neighbor-warnings
Syntax Description
seconds
(Optional) The time interval (in seconds) between repeated neighbor warning messages. The range of seconds is from 1 to 65535.
Command Default
Neighbor warning messages are logged.
Command Modes
Router configuration
Command History
Usage Guidelines
When neighbor warning messages occur, they are logged by default. With this command, you can disable and enable neighbor warning messages, and configure the interval between repeated neighbor warning messages.
Examples
The following command will log neighbor warning messages for EIGRP process 209 and repeat the warning messages in 5-minute (300 seconds) intervals:
router eigrp 209eigrp log-neighbor-warnings 300eigrp router-id
To set the router ID used by Enhanced Interior Gateway Routing Protocol (EIGRP) when communicating with its neighbors, use the eigrp router-id command in router configuration mode. To remove the configured router ID, use the no form of this command.
eigrp router-id ip-address
no eigrp router-id ip-address
Syntax Description
Command Default
EIGRP automatically selects an IP address to use as the router ID when an EIGRP process is started. The highest local IP address is selected and loopback interfaces are preferred. The router ID is not changed unless the EIGRP process is removed with the no router eigrp command or if the router ID is manually configured with the eigrp router-id command.
Command Modes
Address family configuration
Router configurationCommand History
Usage Guidelines
The router ID is used to identify the originating router for external routes. If an external route is received with the local router ID, the route is discarded. The router ID can be configured with any IP address with two exceptions; 0.0.0.0 and 255.255.255.255 are not legal values and cannot be entered. A unique value should be configured for each router.
Examples
The following example configures 172.16.1.3 as a fixed router ID:
router eigrp 209eigrp router-id 172.16.1.3eigrp stub
To configure a router as a stub using Enhanced Interior Gateway Routing Protocol (EIGRP), use the eigrp stub command in router configuration mode. To disable the EIGRP stub routing feature, use the no form of this command.
eigrp stub [receive-only | connected | static | summary | redistributed]
no eigrp stub [receive-only | connected | static | summary | redistributed]
Syntax Description
Command Default
Stub routing is not enabled by default.
Command Modes
Router configuration
Command History
Usage Guidelines
Use the eigrp stub command to configure a router as a stub where the router directs all IP traffic to a distribution router.
The eigrp 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 will restrict the router from sharing any of its routes with any other router in that EIGRP autonomous system, and the receive-only keyword will 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 eigrp stub command, only the route types specified by the particular keyword(s) will be sent. Route types specified by the remaining keywords will not be sent.
The connected keyword permits the EIGRP Stub Routing feature to send connected routes. If the connected routes are not covered by a network statement, 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 the EIGRP Stub Routing feature to send static routes. Without the configuration of this option, EIGRP will not send any static routes, including internal static routes that normally would be automatically redistributed. It will still be necessary to redistribute static routes with the redistribute static command.
The summary keyword permits the EIGRP Stub Routing feature 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 the EIGRP Stub Routing feature to send other routing protocols and autonomous systems. Without the configuration of this option, EIGRP will not advertise redistributed routes.
Note
Examples
In the following example, the eigrp stub command is used to configure the router as a stub that advertises connected and summary routes:
router eigrp 1network 10.0.0.0eigrp stubIn the following example, the eigrp stub command is issued with the connected and static keywords to configure the router as a stub that advertises connected and static routes (sending summary routes will not be permitted):
router eigrp 1network 10.0.0.0eigrp stub connected staticIn the following example, the eigrp stub command is issued with the receive-only keyword to configure the router as a receive-only neighbor (connected, summary, and static routes will not be sent):
router eigrp 1network 10.0.0.0 eigrpeigrp stub receive-onlyIn the following example, the eigrp stub command is issued with the redistributed keyword to configure the router to advertise other protocols and autonomous systems:
router eigrp 1network 10.0.0.0 eigrpeigrp stub redistributedexit-address-family
To exit from address family configuration mode, use the exit-address-family command in address family configuration mode.
exit-address-family
Syntax Description
This command has no arguments or keywords.
Command Default
No default behavior or values
Command Modes
Address family configuration
Command History
Usage Guidelines
This command is used to exit address family configuration mode.
This command can be abbreviated to exit.
Examples
In the following example, the router is configured to exit address family configuration mode:
Router(config-router-af)# exit-address-familyRelated Commands
interface vmi
To create a virtual multipoint interface (VMI) that can be configured and applied dynamically, use the interface vmi command in global configuration mode. To remove a VMI interface, use the no form of this command.
interface vmi interface-number
no interface vmi interface-number
Syntax Description
interface-number
Number assigned to the VMI. The value range for VMI interface numbers is from 1 to 2147483647
Defaults
No VMI is defined.
Command Modes
Global configuration (config)
Command History
12.4(15)XF
This command was introduced.
12.4(15)T
This command was integrated into Cisco IOS Release 12.4(15)T.
Usage Guidelines
VMI Interface Aggregation Point
The VMI interface acts as an aggregation point for multiple PPPoE connections from one or more radios over one or more physical interfaces.
OSPFv3 and EIGRP Route Advertisements
All OSPFv3, EIGRPv4, and EIGRPv6 route advertisements that are received over the PPPoE connections are reported to the routing protocol as coming from a single interface, thus simplifying the routing protocol topology table and providing scalability benefits of each of the routing protocols.
Examples
The following example shows how to create a VMI interface:
interface vmi 1ip address 10.2.1.1 255.255.255.0no ip redirectsno ip split-horizon eigrp 1load-interval 30ipv6 address 2001:0DB8:1:1:FFFF:FFFF:FFFF:FFFE/64ipv6 enableno ipv6 redirectsipv6 eigrp 1no ipv6 split-horizon eigrp 1physical-interface GigabitEthernet 0/0endRelated Commands
ip authentication key-chain eigrp
To enable authentication of Enhanced Interior Gateway Routing Protocol (EIGRP) packets, use the ip authentication key-chain eigrp command in interface configuration mode. To disable such authentication, use the no form of this command.
ip authentication key-chain eigrp as-number key-chain
no ip authentication key-chain eigrp as-number key-chain
Syntax Description
as-number
Autonomous system number to which the authentication applies.
key-chain
Name of the authentication key chain.
Defaults
No authentication is provided for EIGRP packets.
Command Modes
Interface configuration
Command History
Examples
The following example applies authentication to autonomous system 2 and identifies a key chain named SPORTS:
ip authentication key-chain eigrp 2 SPORTSRelated Commands
ip authentication mode eigrp
To specify the type of authentication used in Enhanced Interior Gateway Routing Protocol (EIGRP) packets, use the ip authentication mode eigrp command in interface configuration mode. To disable that type of authentication, use the no form of this command.
ip authentication mode eigrp as-number md5
no ip authentication mode eigrp as-number md5
Syntax Description
