Vlan with Corebuilder 9000 and Cisco 6509

[bluejanus]

We have a C6509 as a core switch with CB9000 switches on different floors. We uplink from each CB9000 via fiber to the 6509. Unfortunately, we have no spare systems to experiment on.

I've seen some of the previous questions concerning vlan interoperability between 3com switches and cisco switches, especially ADB100's reply to Schwiddy (MIS) 08/10/03 (posted 07/24/03) Transport multiple VLans to Cisco 3550 Switch.

I was wondering if anyone has any experience with this sort of interoperability, and if so, would they provide any advice on how to proceed. We attempted to create a vlan, trunk a C6509 port and add ports and tagged backplane ports to the vlan. We resulted in a vlan mismatch error I believe.

 

[TimRegester]

The physical connection should work fine.

To enable 802.1q vlan tagging you will need to set the port on the 6509 as a trunk encapsulated as 802.1q and the port on the CB9000 as an 802.1q tagged port but not as a trunk (trunk means different things in ciscoworld and 3comworld) The vlan index needs close study of the vlan indexes on both switches. VLAN 1 on both is the same with an id of 1 and is used for management in each case.

You should be able to link the two and propogate vlans from the 6509 to the CB9000s with no issues. Be careful to turn off all proprietary spanning tree on the 6509 and config the spanning tree as you want it.