Saturday, March 26, 2011

Lab 70 - RIPv2 Filtering with Passive-Interface

Prerequisites: CCNP level skills.

Topology
Pic. 1 - Topology Diagram.
Icons designed by: Andrzej Szoblik - http://www.newo.pl

Task 1
Configure RIP filtering so that R1 and R2 do not learn 172.16.104.0/24 and 172.16.144.0/24. Do not use any access-list, distribute-list and do not change AD values. R4 should learn all RIP subnets.

Lab Solution

Task 1
Configure RIP filtering so that R1 and R2 do not learn 172.16.104.0/24 and 172.16.144.0/24. Do not use any access-list, distribute-list and do not change AD values. R4 should learn all RIP subnets.

R4 Configuration:
!
router rip
 version 2
 passive-interface FastEthernet1/0
 passive-interface Loopback0
 passive-interface Loopback1
 network 10.0.0.0
 network 172.16.0.0
 no auto-summary
!

Verification:
Pic. 2 - R4's Routing Table.

Notice!
RIP's Passive-Interface prevents a router from sending update out this interface. The router still installs RIP updates advertised by R1 and R2.

Pic. 3 - R1's Routing Table.

Notice!
R1 no longer receives the subnets in question: 172.16.104.0/24 and 172.16.144.0/24.