Guys,
I'm getting the following error message in my environment.. Can you please shed some light on this issue...
%ETHCNTR-3-LOOP_BACK_DETECTED: Loop-back detected on GigabitEthernet0/43.
%PM-4-ERR_DISABLE: loopback error detected on Gi0/43, putting Gi0/43 in err-disable state
Environment:
Got few 3560x and 3750x switches (Source) (GigabithEthernet) centrally connected to a pair of 3560x switches (Destination) on the GigabithEthernet ports...
On the Source switches, the Gi ports are configured as Access ports and IP is assigned on the SVI for that particular VLAN... On the Destination Switch, the switchports are configured as Private VLAN - Isolated...
The Interlink between Destination Switches allows only the private VLAN numbers and native vlan...
Issue:
I receive the above mentioned logs on the Source switches and the ports go err-disabled... If I've 3 source switches, only one port is UP and rest of the 2 Source switch ports go to err-disabled... If I shut and no shut any one of the err-disabled port, the previously UP port goes into err-disabled port while the new port comes up...
Searched through few forums and I found that it could be due to some faulty cables or Keepalive being received on the same port... I tried changing the cables but no use... Disabling keepalive would be an ugly workaround as it doesn't help me to find the root cause...
IOS Version: 15.2(1)E1
Regards,
Sri