Trunking between Cisco and 3COM

kwillacey · ‎05-19-2009

I need to setup some trunks between some Cisco switches and 3com switches. Does anyone have any guides or anything that I need to pay attention to or gotchas on both sides. I wont be configuring the 3COM but it would be nice to be able to help out if a problem occurs.

Thanks in advance.

bretjaquish · ‎05-19-2009

Make sure that the 3COM can create 802.1q trunks.

Find out if the 3COM is manually pruning vlans from the trunk, in case you need to

Find out the native vlan for the trunk.

That's basically it.

switchport trunk encapsulation dot1q

switchport trunk native vlan XX

switchport mode trunk

switchport trunk allowed vlan XX (if pruning)

kwillacey · ‎05-19-2009

The 3COM is capable of 802.1q trunks and i would only need to verify is the pruning and the native vlan. Thanks alot for the info im sure it well help alot if there are any problems.

bretjaquish · ‎05-19-2009

Show interface trunk

Show interface status

Show interfaces XXy/y

These might help you troubleshoot.

You might have issues with spanning-tree between these devices, so it might not be a bad idea for they to be on the same version/flavor of STP.