STP Loop

bava_ccna · ‎05-06-2008

05:39:42: %C4K_EBM-4-HOSTFLAPPING: Host 02:01:00:00:00:00 in vlan 1 is flapping between port Gi2/7 and port Gi2/14,where Gi2/7 and Gi2/14 were connected to two servers.both are in Vlan1.We are using PVST in our LAN.why this problem occurs?

Any help can be appreciated

Regards

Bava

bvsnarayana03 · ‎05-06-2008

Yes its a STP loop. You need to identify the culprit causing the loop.

Check with the command "sh spanning-tree root"

to see if the root for vlan 1 has changed.

bava_ccna · ‎05-07-2008

I found that the root for vlan 1 is not changed and there is no loop also.still the problem exists

Francois Tallet · ‎05-07-2008

It's likely to be a duplicate mac address in your network. The mac address you mentioned seems to be locally administered. So it's probably been generated by an application or a device. Try to find out where the entries are leading to in order to find the culprit(s).

Regards,

Francois