Need help with access-list

[asifchoudhury]

I've configured RIPv2 between R5, R4 and R3.

R5-E0<---------------->R4-E0<--------------->R3-E0

R4 is getting 8 routes (network 189.160.1.0 to 189.160.8.0 ) from R5 and advertising these 8 routes to R3 as a RIP routes. What I am try to do is that instead of R4 sending 8 routes to R3, I am trying to configure R4 so that R4 will send 189.160.0.0/16 only routes to R3. I do not want to use summary command to do this. Below is my config...but it does not work...R3 still sees 8 routes learned from R4. Please tell me what is wrong in my config.

R4#

int E0/0

Ip address 180.120.1.1 255.255.255.0

!

router rip

version 2

network 180.120.0.0

network 189.160.0.0

distribute-list prefix R3 out Ethernet0/0

no auto-summary

!

ip prefix-list R3 seq 5 permit 189.160.0.0/16

!

R3#

int E0/0

Ip address 180.120.1.2 255.255.255.0

!

router rip

version 2

passive-interface default

no passive-interface Ethernet0/0

network 180.120.0.0

no auto-summary

R3# sh ip route

R 189.160.1.0 [120/1] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.2.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.3.0 [120/1] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.4.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.5.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.6.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.7.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

R 189.160.8.0 [120/2] via 180.120.1.1, 00:00:01, Ethernet0/0

[attrgautam]

AFAIK distribute-list will not summarise it will only restrict routes so only way to get summary routes would be to do an auto-summary.

[Georg Pauwen]

Hello,

in addition to Gautam's post, you could also redistribute a static route for the 189.160.0.0/16 into RIP. Either way, you first need the 189.160.0.0/16 route in the RIP database of R4 before you can do anything with it. Your prefix list needs to deny all prefixes for that network with a mask greater than 16.

So basically your configuration options on R4 are:

router rip

version 2

network 180.120.0.0

network 189.160.0.0

distribute-list prefix R3 out Ethernet0/0

-->auto-summary

!

ip prefix-list R3 seq 5 deny 189.160.0.0/17 le 32

or

router rip

version 2

--> redistribute static

network 180.120.0.0

network 189.160.0.0

distribute-list prefix R3 out Ethernet0/0

auto-summary

!

ip prefix-list R3 seq 5 deny 189.160.0.0/17 le 32

!

-->ip route 189.160.0.0 255.255.0.0 Ethernet0/0

HTH,

GP