How to configure route between two subnets on 2960-S?

[ghunioncisco]

Hello everyone,

Please assist me with configuring a working route between two subnets (172.28.0.0/16 and 192.168.0.0/24) on a Cisco Catalyst 2960-S.

Problem: The subnet 172.28.0.0/16 is on VLAN 40 and the clients on this subnet have to access a preconfigured device with an ip in 192.168.0.0/24 subnet. The configuration of this device cannot be changed.

I have an Cisco 2960-S Lan Base (c2960s-universalk9-tar.150-1.SE3) switch (http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_55_se/configuration/guide/swipstatrout.html) that I would like to use to solve this problem.

Is this possible and if so how can I do this?

Thank you and best regards,

Gasper

[ghunioncisco]

can you post a diagram as well as the config from switch and asa.

Thank you but for security reasons I cannot publish configuration in such detail.

[cadet alain]

Hi,

so we'll try to do without  .

b) Ping to 172.28.0.1 from switch. Result:

NOT OK

if you got no int vlan 40 configured this is normal

all other pings not working are the sign than intervlan routing is not  working.

Can you do traceroute from a device in vlan 11 to a device in vlan 40 and vice versa.

Regards.

Alain.

Don't forget to rate helpful posts.

[Richard Burts]

Gasper

Yes writing 192.168.0.0 255.255.255.0 was a mistake on my part. The interface needs to have a host address (as you did it) and not the subnet address. Sorry about my oversight.

In the original post I was assuming that you wanted to route between VLANs on an isolated switch and that would have been easy. But recognizing that the 2960 is part of a larger group of network devices does complicate things. If the device in 192.168.0 network has a default gateway configured that matches the address that you put on the VLAN interface then routing for that device and that subnet should be working. But the complication comes with the device(s) in the 172.28 network. As long as their default gateway points to 172.28.0.1 then they will want to forward through that address to get to 192.168.0 network.

There are a couple of possibilities that should work:

- put a route on the 172.28.0.1 device for 192.168.0.0 with the address of the VLAN interface as the next hop. So the client will forward to its gateway which will then forward back to 192.168.0.1 which will forward to the target device. This means that traffic will go off the switch and back onto the switch. But it works with the least amount of changes to your network.

- make the default gateway of the clients use the 172.28.254.254 address. Then they will forward all "remote" destinations to the 2960 which can forward traffic to 192.168.0 and the 2960 will need a default route configured pointing to 172.28.0.1 as its next hop.

HTH

Rick