Core switches dropping all packets

[rich_harris]

Hi

We have 4 WS-C3560G-24TS running enterprise image running hsrp as our core switches. This week seemingly random once or twice a day ish  all 4 switches are unresponsive, all packets appear to be dropped. Duration of 5 to 20 seconds. then traffic is restored.

Most times we see the following from our syslog server, the error is the same but not always from the same switch...

I cant find any info on the follow.

16/08/2011 14:50:56 10.xxx.xxx.xxx Error 2461: Null mpath for PD LB of Fib 10.xxx.xxx.0/24 Tbl:0

   16/08/2011 14:50:53 10.xxx.xxx.xxx Error 2460: -Traceback= 481CDC 3F7E9C 3F9F08 482BA8 4945B0 494430 486984 482FFC 47A210 47AADC 979ED0 9714A4

  16/08/2011 14:50:56 10.xxx.xxx.xxx Error 2461: Null mpath for PD LB of Fib 10.xxx.xxx.0/24 Tbl:0
   16/08/2011 14:50:53 10.xxx.xxx.xxx Error 2460: -Traceback= 481CDC 3F7E9C 3F9F08 482BA8 4945B0 494430 486984 482FFC 47A210 47AADC 979ED0 9714A4
  

Normally repeated a number of times.

Any Ideas?

Many Thanks

Rich

[John Blakley]

Rich,

I believe traceback errors are usually hardware or IOS related. Have you checked the bug database against your IOS version to see if it's affected? Are all of your switches using the same version?

http://tools.cisco.com/Support/BugToolKit/action.do?hdnAction=searchBugs

You may have to contact Cisco TAC for a resolution...

John

[rich_harris]

Hi John

I did have a look but there are 686 bugs on this ios I tried a few filters but to no avail. This kit has been in place for 18 months with no issue. There are lot of other devices attached.

So I am shooting in the dark a bit. For the time being I am going to change the hsrp priority to make an other switch the master.

I'm thinking hsrp because the whole LAN drops for a number of seconds so it could be while hsrp is failing over.

Thanks

Rich