"IP Nat Ager" using 70% CPU? Why?

[jasonhumes]

Hi

We have a 1751 router with one 10Mb and one 100Mb interface. The 100Mb is set as a 802.1q trunk with many subinterfaces (one for each customer we monitor/manage) and the 10Mb is our Management server subnet. We have 4 management servers each of which have a static NAT translation to each of the subinterfaces on the customer side. We do this through the use of ;

"ip nat inside source static 10.1.1.1 10.2.2.2 route-map customer1map"

and

"route-map customer1map permit 10

match ip add customer1list

set interface f0/0.10" (or whatever subint)"

and

"ip access-list ext customer1list

permit ip 10.1.1.0 0.0.0.255 10.2.2.0 0.0.0.255"

And thats the basic setup, just duplicated with different subints, subnets, etc. Why is this IP Nat Ager process doing anything at all, these are all static translations and should NEVER age out. Please help. Thanks.

[Georg Pauwen]

Hello Jason,

my first thought was that thsi could be a virus...can you do a ´show ip nat translations´ to check for the amount of (active) translations ?

Regards,

GP

[jasonhumes]

Hi

I really cant determine much from that as in reality we monitor 50+ customer networks and am doing SNMP polling, ICMP polling, etc to 1000+ hosts. One thing I did notice though, even though all my nat statements are static, there is ;

"Total active translations: 25595 (141 static, 25454 dynamic; 25454 extended)"

WHy am I seeing dynamic translations? Thanks.