[c-nsp] ASR9K RSPAN via bundle-ether

[Robert Williams]

Hi,

Looking for a quick pointer here, I need to get a remote SPAN session active from one of our ASR9K units across a few Cat6K chassis and into an analyser. We use RSPAN across all the 6Ks without any issues, and from my understanding the ASR needs to egress the captured packets out of a sub-interface and tag them with the RSPAN vlan which the 6K is expecting. Then the 6K will flood the packets in the RSPAN vlan and get them to our analyser like normal. Now on the assumption that is correct so far, I’ll move on to the actual issue.

The only link between this particular ASR and the Cat6k is via a 4x10GB bundle-ether, which has a number of sub-interfaces on it. The spanning feature on the ASR does not support egress mirroring to a destination port which is a bundle-ether, which is handy – so, the question is, what if I were to target the egress towards one of the physical 10GB member ports within the bundle, as a sub-interface of the physical port? From the Cat6k perspective it won’t care as the packets are arriving it will just forward them on the RSPAN vlan. So the only (big) issue is whether or not the ASR will be happy to have one port within the bundle setup to egress mirrored packets?

Oh, and I'm familiar with the mirror-to-pseudowire method, but in this scenario it isn't a particularly nice option for reasons not covered above.

So - any thoughts or suggestions are most welcome - Cheers!


Robert Williams
Custodian Data Centre
Email: Robert at CustodianDC.com
http://www.CustodianDC.com