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How to specify a route on a port when the route overlaps with an internal vlan.

Hi,
I need to define/specify a route on my 3560 Catalyst.  FE0/1 connects to a router which  should be the target for any 10.x.x.x traffic (other than the subnet which has been allocated for my internal use(10.25.x.x)).
 
I have specified the internal network 10.25.x.x as vlan25.

How can I specify that FE0/1is the route for the 10.x.x.x network without getting messages that vlan25 overlaps with the 10 network I want to route to??

The switch is configured for classless routing - a default router is specified for the rest of my (off network) routing.
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Commented:
hi!
it most likely you have 10.25.0.0 255.255.255.0 or 255.255.0.0 on your vlan 25
and on your fa0/1 you have 10.0.0.0 255.255.255.0 network.

please check subnet masks for your networks
And be sure you have "ip classless" and "no auto-summary" commands in. This will allow for VLSM and wont summarize your 10.x.x.x networks into a single class A subnet.

Author

Commented:
Hi,

The company we link to uses has a class A 10.0.0.0 255.0.0.0 network - I have been allocated 10.25.0.0 255.255.0.0 for my internal use / further subnetting.
I can see the overlap but do not know how to address the issue.

If you have a static route for 10.0.0.0 255.0.0.0 to the other company, and you have one of your vlan's or interfaces config'd with a 10.x.x.x address it should work because the router will match the closest route.

Author

Commented:
My problem turned out to be a fundamental understanding of how routing works.  I was indeed wrong to specify a rote to a network on which I was a part.  By using additional subnets I was able to resolve the overlap and specify valid routes.

Author

Commented:
Thank you for trying with a badly composed question.

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