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High CPU usage with NAT on c2600-io3-mz.122-7


i use a 2610 routeur from a long time without any problem with 2600-i-mz.121-9.bin

config :

- cisco 2610 (MPC860) processor (revision 0x203) with 43008K/6144K bytes of memory ))

- 2Mbit upstream link

- the routeur do only NAT ( 8 static and a lot of dynamic )

Since i upgrade to c2600-io3-mz.122-6a.bin or c2600-io3-mz.122-7.bin ( same problem on both version )

-> the cpu usage increase a lot when the number of NAT translations becomes important

to be more specific :

- with about 7000 active translations -> the average cpu is 50%

- or sometines with just 3500-4500 translations -> the cpu can go to 90%

when i do 'clear ip nat translations *' the cpu lower to is normal rate : ~ 10%, so the problem must comes from the NAT process

So it's seems that this new FW/IDS IOS ( i don't use these functionality at the moment ) got problem with NAT

any ideas or same observations ?

Benoit PETIT

Network Ingenior / RS2i

Cisco Employee

Re: High CPU usage with NAT on c2600-io3-mz.122-7

could you capture a 'sh proc cpu' at the time of the problem.

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