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Before I begin, please don't rip me apart for the current configuration. I didn't do it ... I'm just trying to fix without taking it down to redo. :)

I have 2 3560 cats connected via a wireless link. One of the cats is connected to a cisco 3825 router which in turn is connected to the internet. Both cats have one Vlan (vlan1) with an ip of (switch1) and (switch2) and have a default-gateway of On the router, its configured on Gi0/1.1 for a primary of and secondary addresses of,,,,, and and Its a mess but a work in progress to fix without taking everyone down.

On switch2, I have a linux box. When it has an ip address of, say, (correct netmask and router of ... it works and is accessible. If I change the ip and other network information (router to be or anything outside of the subnet it is accessible for about 30 seconds after I bring the interface up but then goes away. It works fine on switch1.

What might be the culprit? I'm happy to provide sanitized switch and router configs.

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Does the trunk between switches HAVE to be wireless? – SpacemanSpiff Dec 3 '10 at 3:55
And do you HAVE to have layer 2 connectivity across segments? Those are layer 3 switches, I'd route between them. – SpacemanSpiff Dec 3 '10 at 3:59
Don't trunk vlan #1, choose any other number but one. – Fran Garcia Dec 3 '10 at 23:17

Are you trunking or access mode between the switches? Regardless, when it times out, look at the mac address table on switch 2 and see what it reads. Make sure that all the VLANs you're using are created on both switches - having multiple secondaries on the router in 1 vlan isn't the best practice and makes it hard to track down problems like this.

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