Advanced EIGRP Configuration

Changing the Interface Delay Value

The interface delay value is used in EIGRP distance calculations. You can modify this value on a per-interface basis. To change the delay value, perform the following steps:

Detailed Steps

	Command	Purpose
Step 1	interface phy_if Example: hostname(config)# interface phy_if	Enter interface configuration mode for the interface on which you are changing the delay value used by EIGRP.
Step 2	delay value Example: hostname(config-if)# delay 200	The value entered is in tens of microseconds. So, to set the delay for 2000 microseconds, you would enter avalue of 200. To view the delay value assigned to an interface, use the show interface command.

Enabling EIGRP Authentication on an Interface

EIGRP route authentication provides MD5 authentication of routing updates from the EIGRP routing protocol. The MD5 keyed digest in each EIGRP packet prevents the introduction of unauthorized or false routing messages from unapproved sources.

EIGRP route authentication is configured on a per-interface basis. All EIGRP neighbors on interfaces configured for EIGRP message authentication must be configured with the same authentication mode and key for adjacencies to be established.

To enable EIGRP authentication on an interface, perform the following steps:

Detailed Steps

Step 1	router eigrp as-num	This creates an EIGRP routing process, and the user enters router configuration mode for this EIGRP process. The as-num argument is the autonomous system number of the EIGRP routing process.
Step 2	network ip-addr [mask] Example: hostname(config)# router eigrp 2 hostname(config-router)# network 10.0.0.0 255.0.0.0	This step configure the interfaces and networks that participate in EIGRP routing. You can configure one or more network statements with this command. Directly-connected and static networks that fall within the defined network are advertised by the ASA. Additionally, only interfaces with an IP address that fall within the defined network participate in the EIGRP routing process. If you have an interface that you do not want to participate in EIGRP routing, but that is attached to a network that you want advertised, see the section Configuring Interfaces in EIGRP.
Step 3	interface phy_if Example: hostname(config)# interface phy_if	Enter interface configuration mode for the interface on which you are configuring EIGRP message authentication.
Step 4	authentication mode eigrp as-num md5 Example: hostname(config)# authentication mode eigrp 2 md5	Enable MD5 authentication of EIGRP packets. The as-num argument is the autonomous system number of the EIGRP routing process configured on the ASA. If EIGRP is not enabled or if you enter the wrong number, the ASA returns the following error message: % Asystem(100) specified does not exist
Step 5	authentication key eigrp as-num key key-id key-id Example: hostname(config)# authentication key eigrp 2 cisco key-id 200	Configure the key used by the MD5 algorithm. The as-num argument is the autonomous system number of the EIGRP routing process configured on the ASA. If EIGRP is not enabled or if you enter the wrong number, the ASA returns the following error message: % Asystem(100) specified does not exist The key argument can contain up to 16 characters. The key-id argument is a number from 0 to 255

Defining an EIGRP Neighbor

EIGRP hello packets are sent as multicast packets. If an EIGRP neighbor is located across a nonbroadcast network, such as a tunnel, you must manually define that neighbor. When you manually define an EIGRP neighbor, hello packets are sent to that neighbor as unicast messages.

To manually define an EIGRP neighbor, perform the following steps:

Detailed Steps

	Command	Purpose
Step 1	router eigrp as-num Example: hostname(config)# router eigrp 2	This creates an EIGRP routing process, and the user enters router configuration mode for this EIGRP process. The as-num argument is the autonomous system number of the EIGRP routing process.
Step 2	neighbor ip-addr interface if_name Example: hostname(config)# router eigrp 2 hostname(config-router)# neighbor 10.0.0.0  interface interface1	This step defines the static neighbor. The ip-addr argument is the IP address of the neighbor. The if-name argument is the name of the interface, as specified by the nameif command, through which that neighbor is available. You can define multiple neighbors for an EIGRP routing process.

Redistributing Routes Into EIGRP

You can redistribute routes discovered by RIP and OSPF into the EIGRP routing process. You can also redistribute static and connected routes into the EIGRP routing process. You do not need to redistribute connected routes if they fall within the range of a network statement in the EIGRP configuration.

To redistribute routes into the EIGRP routing process, perform the following steps:

Detailed Steps

	Command	Purpose
Step 1	router eigrp as-num Example: hostname(config)# router eigrp 2	This creates an EIGRP routing process, and the user enters router configuration mode for this EIGRP process. The as-num argument is the autonomous system number of the EIGRP routing process.
Step 2	default-metric bandwidth delay reliability loading mtu Example: hostname(config)# router eigrp 2 hostname(config-router)# default-metric bandwidth delay reliability loading mtu	(Optional) Specify the default metrics that should be applied to routes redistributed into the EIGRP routing process. If you do not specify a default-metric in the EIGRP router configuration, you must specify the metric values in each redistributecommand. If you specify the EIGRP metrics in the redistribute command and have thedefault-metric command in the EIGRP router configuration, the metrics in the redistributecommand are used.
Step 3	Do one of the following to redistribute the selected route type into the EIGRP routing process. You must specify the EIGRP metric values in the redistribute command if you do not have a default-metriccommand in the EIGRP router configuration.
	redistribute connected [metric bandwidth  delay reliability loading mtu] [route-map map_name] Example: hostname(config-router): redistribute connected [metric bandwidth delay reliability loading mtu] [route-map map_name]	To redistribute connected routes into the EIGRP routing process.
	redistribute static [metric bandwidth delay reliability loading mtu] [route-map map_name] Example: hostname(config-router): redistribute static [metric bandwidth delay reliability  loading mtu] [route-map map_name]	To redistribute static routes into the EIGRP routing process.
	redistribute ospf pid [match {internal |  external [1 | 2] | nssa-external [1 | 2]}]  [metric bandwidth delay reliability  loading mtu] [route-map map_name] Example: hostname(config-router): redistribute ospf pid [match {internal | external [1 | 2] | nssa-external [1 | 2]}] [metric bandwidth delay reliability loading mtu] [route-map map_name]	To redistribute routes from an OSPF routing process into the EIGRP routing process.
	redistribute rip [metric bandwidth delay  reliability load mtu] [route-map map_name] Example: config-router): redistribute rip [metric bandwidth delay reliability load mtu] [route-map map_name]	To redistribute routes from a RIP routing process into the EIGRP routing process.

Filtering Networks in EIGRP

Detailed Steps

	Command	Purpose
Step 1	router eigrp as-num Example: hostname(config)# router eigrp 2	This creates an EIGRP routing process, and the user enters router configuration mode for this EIGRP process. The as-num argument is the autonomous system number of the EIGRP routing process.
Step 2	hostname(config-router)# network ip-addr [mask] Example: hostname(config)# router eigrp 2 hostname(config-router)# network 10.0.0.0 255.0.0.0	This step configure the interfaces and networks that participate in EIGRP routing. You can configure one or more network statements with this command. Directly-connected and static networks that fall within the defined network are advertised by the ASA. Additionally, only interfaces with an IP address that fall within the defined network participate in the EIGRP routing process. If you have an interface that you do not want to participate in EIGRP routing, but that is attached to a network that you want advertised, see the sectionConfiguring Interfaces for EIGRP.
Step 3	Do one of the following to filter networks sent or received in EIGRP routing updates. You can enter multiple distribute-list commands in your EIGRP router configuration.
	distribute-list acl out [connected | ospf  | rip | static | interface if_name] Example: hostname(config)# router eigrp 2 hostname(config-router)# network 10.0.0.0 255.0.0.0 hostname(config-router): distribute-list acl out [connected]	This allows you to filter networks sent in EIGRP routing updates. You can specify an interface to apply the filter to only those updates sent by that specific interface.
	distribute-list acl in [interface if_name] Example: hostname(config)# router eigrp 2 hostname(config-router)# network 10.0.0.0 255.0.0.0 hostname(config-router): distribute-list acl in [interface interface1]	This allows you to filter networks received in EIGRP routing updates. You can specify an interface to apply the filter to only those updates received by that interface.