Cisco Catalyst 1900 Switches - dropping ports
Posted on 2002-03-25
I have 3 Cisco switches, one of which is continually dropping ports.
Setup: Fibre links to switches 1 and 3, switch 2 has two redundant links ie 1 to 2 and 2 to 3.
Switch 2 occassionally drops ports. These ports are unable to ping anything.
I'm assuming that there is a configuration problem with the spanning tree algorithm resulting in ports to be foreced into a blocking state. However, I'm not sure how to troubleshoot this?
I have two vlans in use. As an initial step I removed spantree from both vlans, leaving it active only on vlan 1 (ie the management vlan). This seemed to settle the switch down, however port problems have once again become an issue. All cables and the switch itself have been swapped as well.
Does anyone have any suggestions?