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New Member

Catalyst 4908 backplane issue/bug ?

Hi folks,

I have two 4908s here, one of which is having problems. Gig1 keeps dropping its connection for no apparent reason. Its connected up to 6509 and that seems ok. When the connection goes down everything still looks good - no problems in any normal show commands. We get a few runts on gig1, and then no more traffic passes.

Investigating this some more I checked out the "show mmc np stat" command to look at the backplane controllers.

Looking at the output the Invalid Frames counter is getting up to some very high numbers. I took this to be a very bad thing, especially as its going up when the Invalid Stream ID counter isnt. Every so often it resets back to 0 on everything again, and then a while later wammo, the numbers go up again. Its happenning a bit on all 4 controllers, but is happenning massively on the first (which controls gig1 and gig2 - gig2 isnt used by the way)

Now this looks like a mjor hardware problem, so i was about to declare it an ex-switch and ship it back, when I looked on the nice well behaved switch thats having no problems, and thats doing exactly the same.

Is this a bug in the command or microcode or is this a genuine problem? Any ideas on the traffic suddenly stopping flowing when everything looks ok?



New Member

Re: Catalyst 4908 backplane issue/bug ?

Did you check the duplex settings.?

Refer this troubleshooting doc

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