Lab 49 - EIGRP Filtering with Administrative Distance

Prerequisites: CCNP level skills.

Note!
Use the basic EIGRP configuration (Lab 45 Task 1) in the labs 45-53.

EIGRP filtering can use:

1. Standard ACL.
2. Extended ACL.
3. Prefix-List.
4. Route-Map.
5. Administrative Distance.
6. Passive-Interface.
7. Offset-List.
8. Stub Routing.
9. Selective Stub Routing (stub routing with leak map).

Topology

Pic. 1 - Topology Diagram.

Icons designed by: Andrzej Szoblik - http://www.newo.pl

Task 1

Using Administrative Distance, configure R4 so it does not install 172.16.133.0/24 in the routing table if it is advertised by R1, and 172.16.103.0/24 if it is advertised by R2.

Lab Solution

Pic. 2 - R4's Routing Table.

Task 1

Using Administrative Distance, configure R4 so it does not install 172.16.133.0/24 in the routing table if it is advertised by R1, and 172.16.103.0/24 if it is advertised by R2.

Notice!

Changing the distance for INTERNAL EIGRP prefixes can be done selectively (on per prefix basis).

Changing the distance for EXTERNAL EIGRP prefixes CANNOT be done selectively (either for all or none of them:
router eigrp 1
  distance eigrp 90 255).

R4 Configuration:

!

ip access-list standard R3_L0
 permit 172.16.103.0
ip access-list standard R3_L1
 permit 172.16.133.0
!

router eigrp 1
 network 10.1.124.4 0.0.0.0
 network 172.16.104.4 0.0.0.0
 network 172.16.144.4 0.0.0.0
 distance 255 10.1.124.1 0.0.0.0 R3_L1
 distance 255 10.1.124.2 0.0.0.0 R3_L0

!

Verification:

Pic. 3 -R4's Routing Table.