topic Re: l2 traceroute in a vrf fails in ExtremeSwitching (VSP/Fabric Engine)

l2 traceroute in a vrf fails

Configterminal — Mon, 20 Nov 2023 13:40:42 GMT

Hello, I'm trying to figure out why my l2 traceroute fails within a vrf. I have cfm configured on my VOSS switches as so:

"cfm spbm enable"

And when I run "l2 traceroute ip-address google.com" it works just fine. But when I run: "l2 traceroute ip-address google.com vrf vrf-name-here" I get:

Error: MEP does not exist.

Is there any way to configure CFM to work within a VRF/L3 VSN?

Re: l2 traceroute in a vrf fails

EXTR_Paul — Tue, 21 Nov 2023 20:31:13 GMT

l2 traceroute only works between SPBm nodes, its part of the OA&M features of SPBm. The L2 Traceroute only words with the SPBm node name. Not DNS or IP address. It only cares about SPBm switches.

you want "TRACEROUTE".

Re: l2 traceroute in a vrf fails

Configterminal — Wed, 22 Nov 2023 14:15:05 GMT

Thanks Paul, the thing is I am able to do it within the GRT to any destination, and it'll show me the L2 path e.g.:

LAB-ROUTER:1(config)#l2 traceroute ip-address google.com

Please wait for l2trace to complete or press any key to abort

L2 Trace Statistics : IP 142.250.80.46, paths found 1
==================================================================
LAB-ROUTER-6 (dc:b8:08:aa:bb:cc), vlan 4051

0 LAB-ROUTER (a8:c6:47:dd:ee:ff)
1 LAB-ROUTER-2 (dc:b8:08:ab:cd:ef)
2 LAB-ROUTER-3 (48:9b:d5:aa:aa:aa)
3 LAB-ROUTER-4 (48:9b:d5:bb:bb:bb)
4 LAB-ROUTER-5 (48:9b:d5:cc:cc:cc)
5 LAB-ROUTER-6 (dc:b8:08:dd:dd:dd)

But when trying to the same within a VRF, I get:

LAB-ROUTER:1(config)#l2 traceroute ip-address google.com vrf VRF-NAME-HERE

Error: MEP does not exist.

If this functionality isn't available, what is the best way to determine the L2 path within the context of a VRF?

Re: l2 traceroute in a vrf fails

Configterminal — Wed, 22 Nov 2023 14:42:37 GMT

I actually just read through this support article https://extreme-networks.my.site.com/ExtrArticleDetail?an=000094392 and found:

The l2 ping/traceroute for an IP address only works for an address whose next-hop is an ISIS route pointing to a remote BEB

This explains why the l2 traceroute is failing within a VRF in my example.

Thanks for your help @EXTR_Paul