I am having high CPU utilization (sometimes 90% or more) on a 1841 router. Checking with "show processes cpu" I found out that about 2% is caused by processes and all the rest is because of interrupts. So I checked NAT translations and there are a lot of them so I think maybe that is the problem. My internal LAN is /24 and all traffic is NATed with overload to one public IP address.
A lot of the translations seem to be from one different port on every IP address to different destinations from each IP address, for example:
udp x.x.x.x:60630 x.x.x.250:60630 x.x.x.x:x x.x.x.x:x
Also about an hour ago I cleared ip nat translations and statistics, and "show ip nat statistics" gives me the following:
Total active translations: 1834 (0 static, 1834 dynamic; 1834 extended)
Hits: 312162 Misses: 11021
CEF Translated packets: 315723, CEF Punted packets: 14884
Expired translations: 13256
-- Inside Source
[Id: 2] access-list xx interface FastEthernet0/0 refcount 1834
[Id: 1] route-map XXX interface FastEthernet0/0 refcount 0
Queued Packets: 0
Do any has had any problem like this or can give me any advice on what to look for?
Thanks a lot,