[c-nsp] Cisco 7201 (G2) Traffic Performance (High CPU Utilization)

[Troy Boutso]

Thanks for all the replies. I definitely feel better reading that as the
traffic patterns increase the "CPU should't" necessarily grow at the same
rate.
Here is the interface config for the WAN link

!
interface GigabitEthernet0/3
 description WAN LINK TO ASIA
 mtu 2000
 ip address 10.12.188.102 255.255.255.252
 ip mtu 1500
 ip ospf network point-to-point
 ip ospf 1 area 1
 load-interval 30
 speed auto
 duplex auto
 negotiation auto
 mpls ip
 service-policy output SHAPE194MBPS
!

** yes I have tried removing the shaping and didn't notice a big difference
in CPU utilization 2-3%.


Here is the Port-Channel facing the switch stack:

!
interface Port-channel10
 description PortChannel Trunk To Core Switch
 mtu 2000
 no ip address
 no negotiation auto
!
!
interface Port-channel10.50
 description L3 To Core Switch (VLAN50)
 encapsulation dot1Q 50
 ip address 10.12.188.53 255.255.255.252
 ip mtu 1500
 ip ospf network point-to-point
 ip ospf 1 area 0
!


I did notice something very strange with another cluster of routers last
night when I was commissioning them.
Same setup, port-channel trunks to a core switch with sub-interfaces
running over them.

I was seeing some issues with bringing up an 3-way OSPF broadcast w/MPLS
LDP. The OSPF would come up fine BUT, the LDP wouldn't come up for all 3
peers. Only 2 of them.
It wasn't until I shut one of the physical interfaces on all the routers in
the channel-group that it all started to work. I proceeded to un-shut the
physicals and it continued to work.

This was not a once off incident. I had the exact same issue 30 minutes
later on another site.

Which leads me to think that port-channels may behave strangely when being
brought up initially on this instance.

I'm going to try to bounce these boxes off peak and report back.


Thanks for the assistance.