ISR 4451 latency

[svbyrne]

hello

we have an ISR4451-X/K9 running isr4400-universalk9.03.13.02.S.154-3.S2-ext.SPA.bin

we have an  ISR4451-X-4x1GE module installed

g0/0/0 presenting rj45 to the LAN

g0/0/1 presenting an SX SFP to the WAN

when the customer moves g0/0/0 into a new firewall context we see high latency and packet loss the WAN interface between the  CE -- PE which are  directly connected peers

there is no latency or packets loss on the LAN interface

this latency on the WAN interfaces  remains a problem even  with the LAN interface shutdown

the fix is to move the LAN interface back to the original firewall context

Q do you think we are running into a software defect ?

[Joseph W. Doherty]

It might be the module slot doesn't have the bandwidth and/or buffering capacity of the built-in ports.

The 4451, itself, also doesn't have the forwarding capacity of supporting four gig duplex ports, although from what you described, doesn't sound like you're hitting that limit.

[svbyrne]

Joseph



Thanks



I checked the load on the router interfaces when g0/0/0 was moved - it was low 38k



The latency is triggered when g0/0/0 is moved into a new firewall context



The latency continues even when g0/0/0 is disconnected or shutdown

[Joseph W. Doherty]

Interface load under what time period? Microbursts won't generally show as loading an interface, although you might see interface drops.

That said, seeing the issue continue, after shutting the interface, makes it more complex.

Often extremely difficult trying to debug an issue like this without "being there".

Do you have a Cisco support contract? If so, open a TAC case.