Enabling a VLAN Disables the other

[amiralisetoudeh]

Hi,

We have a 2950 Switch connected to a Cisco router, and a Mitel server.

The switch has VLAN 1 and 100 configured on it - all ports being in both. We have voice traffic on VLAN100.

When I try to enable VLAN100, VLAN1 shuts off.

All ports are configured as access-ports.

My goal is to have the switch forward packets to the router to a branch site, if needed, and vise versa.

Am I going to have to enable trunking and interVLAN routing on both the switch and the router?

Thanks,

Al

[Richard Burts · Accepted solution]

Al

It sounds to me like you are doing the right things. If you can not access the Mitel, then I suspect that it is some issue on the Mitel. If they are going to check the Mitel server I believe the obvious things to check include that its configured IP address and netmask are as you expect them to be and that they match what you configured on the router subinterface. Also check to verify that the default gateway configured is the address configured on the router subinterface.

I also wonder if it could be an issue with ping. Some servers are configured in a "hardened" mode and may not respond to ping as a policy. While tracert from a Windows PC uses ping (and is not useful for the immediate purpose) traceroute from the Cisco router uses UDP packets. So it might be useful to traceroute from the router to the Mitel and see if there is any response. Or have the folks at the site see if they can access anything from the Mitel.

HTH

Rick

[boblutton]

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[amiralisetoudeh]

Great information, as always...

Things are looking good here...

I had the guys at the branch convert the port connected to Mitel to a trunk, and now both Mitel's at each site can see eachother. (Yes!)

The only thing is that the voice traffic is not traversing the link between the branch and main site... I think once the routers have routes to the voice subnets they should be able to forward voice data back and forth... the admins on site said it's most likely a signalling configuration on the line with the telco - I'm not quite sure about that though.

They're having the telco personel go check that because they don't have logon access to the Mitel's. So I'm basically waiting to hear back from them.

Wonderful help Rick... you rock!

Al

[Richard Burts]

Al

Thanks for the kind words (and for the ratings). And thanks for using the ratings to indicate that the problem has been solved. It makes the forum more useful when people can read about a problem and know that a solution was found and to be able to read the solution along with the problem.

I am not clear about the topology. In general if the VLANs are correctly configured, if trunking is correctly configured, and if the routers have the correct routes I would expect the voice traffic to flow.

I notice that you say that the port connected to Mitel is now a trunk (at least I think that is what you are saying). I wonder if Mitel might be doing something with tagging or not tagging frames that is confusing things.

HTH

Rick