Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements
Webcast-Catalyst9k
New Member

Cisco 2950 v12.1(20)EA1a err-disable bug??

Hi All

We change a CPE router connected to a switch 2950 to a new CPE router. But after the change on teh switch we have :

Jun  9 14:10:35.091: %ETHCNTR-3-LOOP_BACK_DETECTED: Keepalive packet loop-back detected on FastEthernet0/5.
Jun  9 14:10:35.091: %PM-4-ERR_DISABLE: loopback error detected on Fa0/5, putting Fa0/5 in err-disable state
Jun  9 14:10:36.091: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/5, changed state to down
Jun  9 14:10:37.099: %LINK-3-UPDOWN: Interface FastEthernet0/5, changed state to down

when I put back the hold router still same issue.

I can bring up the interface with no keepalive, but still issue with the loop

If I change manually the mac address then the interafce came up, but still not passing any traffic

Any idea?

Ta

Mel

1 REPLY
Hall of Fame Super Silver

Re: Cisco 2950 v12.1(20)EA1a err-disable bug??

Hello Melanie,

there is a bug affecting some low end switch platforms with these effects (but  on fiber based ports if I remember correctly)

However, you already have found the workaround that is to disable keepalive on the interface

Hope to help

Giuseppe

187
Views
0
Helpful
1
Replies
CreatePlease to create content