The Router Eigrp [As Number] Cisco command

The Cisco command 'router eigrp [AS_number]' is used to enable Enhanced Interior Gateway Routing Protocol (EIGRP) routing on a Cisco router and assign an autonomous system (AS) number to it. Here's a more detailed explanation:

Command Syntax:

router eigrp [AS_number]



  1. Enter the 'configure terminal' command to enter global configuration mode.
  2. Use the 'router eigrp [AS_number]' command to enable EIGRP and assign an AS number.
  3. Configure additional EIGRP parameters as needed, such as network statements, redistributive routes, etc.
  4. Use the 'end' command to exit configuration mode and save your changes.

Type of Equipment:

Command Details:

Additional Information:

router eigrp [AS_number] Usage Examples

1. Enabling EIGRP on a Router:

Command: router eigrp 10

Explanation: This command enables EIGRP on a router and assigns it to autonomous system 10. The value "10" can be replaced with any valid AS number.

2. Configuring EIGRP Network Parameters:

Command: router eigrp 10 network

Explanation: This command configures the network parameters for EIGRP in autonomous system 10. It specifies the network address "" and the subnet mask ""

3. Redistributing Connected Routes into EIGRP:

Command: redistribute connected metric 100 1000 255 1 1

Explanation: This command redistributes routes learned from directly connected networks into EIGRP. The "metric 100 1000 255 1 1" specifies the default metric attributes for the redistributed routes.

4. Summarizing Routes in EIGRP:

Command: ip summary-address eigrp 10

Explanation: This command summarizes the routes matching "" in EIGRP autonomous system 10. The summarized route will be advertised with a shorter prefix.

5. Configuring EIGRP Stub Routes:

Command: eigrp stub

Explanation: This command configures the router to be an EIGRP stub router. Stub routers only accept routes from their upstream neighbors and do not advertise their routes further.

6. Configuring EIGRP Default Routes:

Command: default-information originate

Explanation: This command originates a default route "" via EIGRP. The default route will be advertised to all EIGRP neighbors.

7. Configuring EIGRP Route Maps:

Command: route-map RM-1 match ip address

Explanation: This command creates an EIGRP route map named "RM-1" and matches packets with an IP address "" Route maps are used to control the advertisement and acceptance of routes.

8. Applying EIGRP Route Maps:

Command: router eigrp 10 distribute-list RM-1 out

Explanation: This command applies the route map "RM-1" to outgoing EIGRP updates in autonomous system 10. This allows the router to filter routes before they are advertised to neighbors.