Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
New Member

VLAN Routing

I have this situation that goes like this

We have a network ( VLAN 10) and, secondary( VLAN 11) as vlan addresses which communicate with each other via MSFC.

There is another network on another router with Primary address10.104.240.2/20 and as secondary address. These are also on VLAN 11. So in effect, all those on network can reach the 10.104 network when we add static route to devices on the VLAN 11 network as their gateway is a firewall in that address range so we add a static route to the network.

Pldease how do I make devices on Vlan 10 get to the network.

I tried putting a secondary address in the range network on the VLAN 10 just like VLAN 11 but it will not accept it and keeps saying the address alreadsy exists on VLAN 11 which it does.

Please help.

Cisco Employee

Re: VLAN Routing

It is a bit hard to follow your description, so let me know if my analysis of it is incorrect.

It looks like you have overlapping IP subnets in vlan 11, is that correct?

ie, all these subnets are in vlan 11:

And your problem is that from in vlan 10 you can't access the subnet, correct?

So there are really two things you need:

- a route to in the MSFC where vlan 10 is configured

- a route to in the other router where your subnet is configured

New Member

Re: VLAN Routing


On the Switch with MSFC, we have


In VLAN 11, we have 2 network, sec


In Vlan 10, we have

On a separate Router


and then we have a router plugged into the Switch with addresses sec - Vlan 11.

Thereby devices on A are able to communicate with devices on C via the 172.30.x.x addresses.

When I try to put in a sec address for 172.20 onto VLAN 10, it does not accept it as it says, the address range is already on VLAN 11.

What I want is for devices on B to be able to communicate with devices on the 10.104.240.x network.

Please let me know if you need any more information. This is really driving me ......

Thank you.

CreatePlease to create content