I have a 3845 router with 256 DRAM and 64 flash. IOS is 12.4(20)T advsecurity. This router is serving as a hub to more then 150+ branches. Firewall is connected to this router and beyond the firwall are 2 internet connections as well.
At peek times, we see the utilization reaching 80-90%, Yesterday i saw it to be at 97%. When i did show processes cpu sorted, the top two processes were
1) IP Input
2) OSPF 100 router
I am confused that when CPU utilization goes high, does it mean that DRAM needs to be upgraded. I mean What is the relation between CPU utilization and DRAM of the router ?
Kindly note that i have cef enabled on all interfaces and globally. I check the router interfaces using show int and dont see any buffer overflow conditions. I do see interfaces dropping the packets. Currently we dont have a support contract and cant open the tac case but i need some urgent help on this. Kindly with your expertise let me know, what shall i do. And also for my confusion, tell me the relation between CPU utilization and DRAM of the router.