Intervlan routing on C3750

Posted on 2009-02-12
Last Modified: 2012-05-06
I am trying to do intervlan routing on my switches but it doesn't seem to be working.

These are the devices that are involved: Router, C3750 Switch, C3548 Cloud, PC1 and PC2.

We have incoming connection from Router to C3750 which connects to C3548 Cloud (hereby referred as C3548s. DG = Default Gateway from hereby.

Router's Fa0/1 connects to C3750's Gi1/0/1(Using copper to fiber convertor).
Fa0/1 IP is and Gi1/0/1 IP is and they are in Vlan 666.

C3750's Gi1/0/2 connects to C3548's Gi1/0/2
Connection is trunk, dot1q, native vlan 1, no other allowed vlans.

Vlan1 interface on C3750 is defined as DG is
Vlan1 interface on C3548 is defined as DG is
Rest of the C3548 Cloud has Vlan1 interface as 10.1.1.*/23 and DG is

PC1 is in Vlan 1 with IP and DG
PC2 is in Vlan 1 with IP and DG

PC1 and PC2 should be able to connect to external network via the vlan 666 and through the Router.

I have enabled "ip routing" in C3750. But it doesn't seem to be the way to do it. What other necessary steps do I have to do in C3750 so that the traffice from Vlan1 is routed to Vlan666 and out of the router?

Are the IP address and DGs on the LAN correctly assigned? I want intervlan routing in C3750 to route the traffic from vlan1 to vlan666. Hence I have set the DG to be on a different subnet then the Vlan1 interface.

You can refer to the attached diagram for more clarity on this. Any help on this would be great.. Thanks in advance..
Question by:coolgeek84
    LVL 5

    Accepted Solution

    the default route on the 3750 should be the next hop interface address, so change it to

    ip route

    On the router you will need a route for the network pointing to the 3750

    ip route

    A default gateway when configured on a switch is used to route traffic from the device itself to other networks, things like monitoring traffic, RADIUS/TACACS traffic etc
    LVL 1

    Author Comment

    Ok, I will try this later on and see how it goes.
    LVL 1

    Author Closing Comment

    Sorry for the delay and thanks for your help! =) Have a good day...

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