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High CPU usage on PIX 6.2.2

Our PIX has extremely high CPU usage, mostly 99%, with lots of interface overruns. Is there a way to track what is causing such high CPU usage. We have a VPN tunnel running between the sites as well. For that very reason, it keeps locking up every now and then.

Any ideas why this would be happening?

Community Member

Re: High CPU usage on PIX 6.2.2

Please see this link:

What's your interface MTU?

Any other suspect error on pix interfaces?

Community Member

Re: High CPU usage on PIX 6.2.2

Virus(es) on an inside or dmz host can peg the cpu of the pix. You can try putting an acl on the inside (and/or dmz) interface, and deny some of the commonly attacked ports.

If valid traffic is not passing through the pix, you can unplug the inside interface cable; see if that drops the cpu. Patch all inside hosts, and use up-to-date anti-virus.

Note that 6.2.3 is General Deployment code now.

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