Hi There,
I'm a bit lost why adding a simple NAT config onto our cisco 7206VXR can cause the CPU utilization to go from 25% to 50% and higher, causing the router itself to become sluggish and unresponsive at times. Removing the "ip nat outside" config from the outside interface restores the CPU utilization back to normal.
#sh ver
Cisco Internetwork Operating System Software
IOS (tm) 7200 Software (C7200-IS-M), Version 12.3(22), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by cisco Systems, Inc.
Compiled Wed 24-Jan-07 20:17 by ccai
Image text-base: 0x60008AF4, data-base: 0x61D44000
ROM: System Bootstrap, Version 12.2(8r)B, RELEASE SOFTWARE (fc1)
BOOTLDR: 7200 Software (C7200-KBOOT-M), Version 12.2(15)B, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)
Snips of the NAT config:
interface GigabitEthernet0/1.11
encapsulation dot1Q 11
ip address x.x.x.x 255.255.255.240
ip nat outside
ip flow ingress
no cdp enable
interface GigabitEthernet0/1.12
encapsulation dot1Q 12
ip address 192.168.12.1 255.255.255.0
ip nat inside
ip flow ingress
no cdp enable
ip nat inside source list 50 interface GigabitEthernet0/1.11 overload
access-list 50 permit 192.168.12.0 0.0.0.255
Please see attached for "sh ip int" and "sh process cpu" output.
Thank you in advance.
Cheers.
Andy
