IEEE 802.1ag CFM or Connectivity Fault Management is very popular in the provider space to troubleshoot MPLS networks. Avaya has implemented CFM for all their switches that runs SPBM. We are facing here the same problem that we have in troubleshooting MPLS networks, we need to figure out wich path across a given network the traffic is forwarded. In SPBM you can have multiple redundant equal cost multipath wich will be presented for a standard trace from a connceted host like a single hop. CFM gives you the ability to run Layer2 pings and traceroutes across your SPBM fabric.
To setup CFM for Avaya switches you need this command:
cfm spbm enable
I would recammand to enable cfm on all devices in a SPB network. Now you can use the L2 ping and trace commands. You need the SBM B-VLAN as a paramater. Here it can be that you have an other path across your network for the second b-vlan. The routername is the sysname of the switch, here it is an good idea to have something human readable that makes troubleshooting more easy. Note the routernodename is case sensitive.
ERS8k:5# l2 ping vlan 4051 routernodename VSP7k Please wait for l2ping to complete or press any key to abort ----00:10:00:32:00:00 L2 PING Statistics---- 0(64) bytes of data 1 packets transmitted, 1 packets received, 0.00% packet loss round-trip (us) min/max/ave/stdv = 1765/1765/1765.00/ 0.00 ERS8k:5# l2 traceroute vlan 4051 routernodename VSP7k Please wait for l2traceroute to complete or press any key to abort l2traceroute to VSP7k (00:10:00:32:00:00), vlan 4051 0 ERS8k (00:10:00:11:00:00) 1 VSP8k (00:10:00:12:00:00) 2 VSP7k (00:10:00:32:00:00) ERS-11:5#l2 traceroute vlan 4052 routernodename VSP7k Please wait for l2traceroute to complete or press any key to abort l2traceroute to VSP7k (00:10:00:24:00:00), vlan 4052 0 ERS8k (00:10:00:11:00:00) 1 ERS48 (00:10:00:21:00:00) 2 VSP7k (00:10:00:24:00:00)
I hope that Avaya will implement also in future Continuity Check Meassage CCM, Delay Measurement DM and Y.1731 for performance monitoring like jitter, latency and frame loss.