Routing Performance - 7206vxr

[pwelmarcus]

Hi there

I have a minor issue whereby we have a Cisco 7206VXR (NPE-G1 acting as our EDGE isp router, we are seeing minimal packet loss when pinging to any ip on the gi0/2.xxx dot1q interface within the respective vlans (roughly 1-2 packets out of a thousand). The basic physical topology is as follows:

ISP Peer >>>>>>> gi0/3 7206 vxr gi0/2 >>>>>>>>> gixx trunk 3560e gixx trunk >>>>>>>>>>>>> customer vlans

we dot1q the gi0/2 interface on the 7206 to provide the individual customer ISP vlans. looking at the routing performance data sheets the router is capable of running 521.22 Mbps (this is without the QoS, ACL and additional functions/services) Were seeing inbound traffic from the ISP Peer of around 300Mbps and outbound at around 70 Mbps. Obvioulsy this traffic flows through the router via the gi0/2 interface so the reverse traffic volumes are observered here (300Mbps out and 70 in). Is this routing performance an aggregate of all interfaces ie (300+300+70+70) = 740M or is it based on routed packets in which case it would be 300+70 = 370. Having performed relevant physical checks and config checks there are no obvious issues. The router itself has a full BGP routing table, has various ACL's and performs a fair amount of QoS policing to limit the various subinterface networks. CPU usage is relatively high around 50% and the memory of is running at about 75%. Someone suggested we replace the processor however I believe the router is not capable of handling the amount of traffic hence the

minimal amount of packet loss. Any advice appreciated.

[paolo bevilacqua · Accepted solution]

Seems to me that you need an NPE G2, or full router upgrade.

Sometime using service provider images helps, but it's not sure.

[vmiller · Accepted solution]

Agree with Paolo, I'd say you are getting about all you can out of the platform. (I'm suprised some of the numbers aren't higher).  My personal preference would be to not even bother with the G2, but migrate platforms.

[pwelmarcus]

Thanks guys, long term looking at ASR's but for now may have to go for the G2 to at least alleviate the issue short term

[paolo bevilacqua]

Thank you for the nice rating and good luck!

[Joseph W. Doherty]

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Posting

As the others have noted, for a 1 Mpps processor, your CPU loading seems "in the ball park" for your traffic load.

In theory, the -G2 should offer twice the forwarding performance, but it uses a different processor than the other 7200 NPEs, and the 2x rating might be a little optimistic although it's much faster than the -G1.

If you have a VXR, "fastest" upgrade would be the NSE-1 (of course, also EoL).

ASR1K is the next step up, but the recently announced 4451-X looks to fill the performance niche between the 3945E and the ASR (performance wise, looks somewhat better than a NPE-G2 - up to about 3 Mpps).