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LlewellynIT

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How to setup RIPv2 between 3Com 4500 and Cisco 2811?

I have a Cisco 2811 routing all internet traffic, and a 3Com 4500 layer 3 switch handling all internal traffic. There are static routes to handle everything, and all works well. Currently I am using static routes however and I'd like to switch this over to RIPv2 as I hear it is more "dynamic". I have enabled RIPv2 on both devices and declared which networks to listen for, but neither device is getting any RIP updates from anything else. All ip route tables show static or connected entries. What do I need to do to get this working between these two devices?
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Rick_O_Shay
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Usually you have to enable RIP 2 globally on each router (router rip command) and on the interface common to the two routers you then need to set up to send and recive RIP2 packets. Some routers have send and receive as a separate parameter in the config.
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LlewellynIT

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On the Cisco 2811 there is no way to associate RIP with an interface, but it is globally enabled as V2 and I have added the appropriate networks.

On the 3Com 4500 I associated the interface in question with RIPv2. I did "rip input" and "rip output" but that added nothing to the configuration that I saw.

I do see a RIP entry on the 2811 now though, but it's only pulling some of the networks. I see no RIP entries on the 3Com.
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The networks are under rip in the config:

[3comL3] rip
[3comL3] network 10.1.1.0
[3comL3] network 10.1.2.0
I do have the networks already defined on the 3Com 4500.
Static routes have higher priority so if you received a route for the same network via RIP the static would be put into the route table. Do you have a test network you can delete or disable the static route for?
When I type "show ip route" on the 2811, I see 2 of the VLANs in question are being pulled via RIP, but 1 of them is not. The settings are identical on VLAN 2,3, and 10 on the 3Com 4500. Why would it only be broadcasting VLAN3 and 10? (VLAN 3 and 10 have the same first two quartets - 192.168.x.x) so it's pulling them both as a 192.168.0.0/16.
Is there a network statement for the VLAN 2 network on the router where it lives? If not it won't get advertised by RIP. Also if it is directly attached to the router you are on it won't show as received from RIP in that router.
Yes there is. All of the subnets in question have been set up identically, yet here is the result of "show ip route" on our primary Cisco 2811 Router. The static routes will be removed once I can determine RIPv2 is working. Looks like it "sorta" is. As I mentioned before all settings on the 3Com are identical for each VLAN.

We have 4 subnets :
192.168.1.1 (between Router and Layer 3 Switch)
192.168.2.1 (primary subnet)
192.169.1.1 (secondary subnet)
192.169.2.1 (voice subnet)

      xx.x.x.x/29 is subnetted, 1 subnets
C       xx.x.xx.x is directly connected, FastEthernet0/0
     192.168.0.0/24 is subnetted, 2 subnets
S       192.168.2.0 [1/0] via 192.168.1.2
C       192.168.1.0 is directly connected, FastEthernet0/1
     192.169.0.0/16 is variably subnetted, 3 subnets, 2 masks
S       192.169.2.0/24 [1/0] via 192.168.1.2
S       192.169.1.0/24 [1/0] via 192.168.1.2
R       192.169.0.0/16 [120/1] via 196.168.1.2, 00:00:23, FastEthernet0/1
S*   0.0.0.0/0 [1/0] via xx.xx.xx.xx
It looks like something has the wrong mask where that /16 is showing up. But you are getting that route via RIP from the 3Com. Is the switch showing any success from RIP?
The switch is showing nothing from RIP. All routes I see active on it are static or direct connection.

I tried removing the static routes from the 2811 and that seems to have fixed RIP on it's side. When I removed the static route from the 3com 4500 though, the link was broken between them. So something is definitely still up on the switches side. Definitely looks like the 3Com has an output, but no input from RIP.

"show ip route" from Cisco 2811 now

Gateway of last resort is xx.xx.xxx.xx to network 0.0.0.0

     xx.xx.xx.xx/29 is subnetted, 1 subnets
C       xx.xx.xx.xx is directly connected, FastEthernet0/0
     192.168.0.0/24 is subnetted, 2 subnets
R       192.168.2.0 [120/1] via 192.168.1.2, 00:00:28, FastEthernet0/1
C       192.168.1.0 is directly connected, FastEthernet0/1
     192.169.0.0/24 is subnetted, 2 subnets
R       192.169.2.0 [120/1] via 192.168.1.2, 00:00:28, FastEthernet0/1
R       192.169.1.0 [120/1] via 192.168.1.2, 00:00:28, FastEthernet0/1
S*   0.0.0.0/0 [1/0] via xx.xx.xx.xxx
You need rip input on the interface which should be on by default if that interface has rip enabled with the "rip network" command. You need to match RIP version with what the Cisco is using, should be Version 2. You need to make sure you also match broadcast or multicast type on the interface. So that should look like "rip version 2 broadcast" or "rip version 2 multicast".

On the Cisco you need to set RIP send and Receive to V2 also:
ip rip send version 2
ip rip receive version 2


Can you attach the config?
RIP is working, but I was under the wrong impression that the Layer 3 switch would be pulling info from RIP when it shouldn't. The Layer 3 switch has all the subnets locally defined so there is nothing to pull using RIP.
RIP was setup correctly apparently the whole time. Not sure what I was expecting the layer 3 switch to pull via RIP.