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New Member

VLAN Issue

I have a 6500 switch, and two 2924 switches. There are two ports setup as VLAN40 in my 6500. On those two 2924 switches, I didn't configure any VLAN's on them. I assigned two different IP addresses on each 2924 interface VLAN1, and hostnames on these two 2924 switches. The IP addresses on those 2924 switches are within VLAN40. I connect these two 2924 switches on that two VLAN40 ports on 6500. They are not trunked. All these three switches are configred as VTP server with same domain name. Problem: these two 2924 switches cannot be reached at the same time. If I shut down 2924 "A", then I can ping 2924 "B", vice versa. They have different IP addresses and hostname, why I can only reach one switch at a time. Please advice. Thanks.

New Member

Re: VLAN Issue


I think it has something to do with 'Spanning-Tree'. It seems that in your case one of the two ports is being blocked when the two 2924's are connected and powered on.

You can try and add the command 'no spanning-tree vlan40' on your three switches.

Best regards

Edwin van Wijk

New Member

Re: VLAN Issue

Both ports on 6500 are in forwarding mode. Any inputs, idea will be appreciated. Thanks.

Re: VLAN Issue

Make the 6500 the STP root (set spantree root). Do a show spantree on all switches to make sure all ports at both ends are forwarding and that the 6500 is seen as the root. Do a show cam to make sure they see each other. Make the 6500 the default gateway.

Also, what was the reason you didn't make them all in the same vlan?


New Member

Re: VLAN Issue

They are on the same VLAN.

Both switches are defective. Problem resolved after replacing both switches. Thanks

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