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New Member

Hour timeout with CSS11000

My company has a handful of old CSS11000s (11150s, I believe) that we've seen an issue with a few times during initial activation. In short, when we first plug a new CSS11000 into our major network, it doesn't pass traffic for an hour. Then, without our changing anything, it suddenly starts working. In both cases where this occurred, the CSS11000 was plugged into our upstream switch, a Cat6509. Anyone have any idea why this happens?

Cisco Employee

Re: Hour timeout with CSS11000

If your CSS is replacing another equipment [reusing ip addresses] you have to clear the arp table of upstream gateway so it can detect the new device.

If you don't you have to wait for the arp entry to timeout which may take 1 hour.

Next time this happen, check arp table and get a sniffer trace in front of the CSS to verify that traffic is coming in.


New Member

Re: Hour timeout with CSS11000

That's not it. Out of the two times we've seen this happen, the arp cache was manually cleared the one time the CSS was a replacement for another. Also, the upstream device has a 4 hour default arp timeout.

Cisco Employee

Re: Hour timeout with CSS11000

then, next time, do some troubleshooting.

Capture sniffer traces to see if the packets are coming in.

Could also be the arp cache on the server.

And when you replace one CSS with another, the mac address will still change.


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