The 7210 SAS-Mxp, 7210 SAS-R6, 7210 SAS-R12, 7210 SAS-T, and 7210 SAS-Sx/S 1/10GE and 7210 SAS-Sx 10/100GE operating in standalone mode support bidirectional forwarding detection (BFD) to monitor individual LAG link members, which speeds up the detection of link failures. When BFD is associated with an Ethernet LAG, BFD sessions are established over each link member; sessions are called micro-BFD (uBFD) sessions. A link is not operational in the associated LAG until the associated micro-BFD session is fully established. The link member is also removed from the operational state in the LAG if the BFD session fails.
If BFD over LAG links is configured before the LAG is active, a link will not become operational in the associated LAG until the associated BFD session is fully established. If a LAG link is already in a forwarding state when BFD over LAG links is enabled, the forwarding state of the LAG link is not influenced until the uBFD session is fully established. A setup timer is started to remove the link from the LAG in the case where the uBFD session is not set up in time. By default, the setup timer value is set to never expire.
When configuring the local and remote IP addresses for BFD over LAG link sessions, the local-ip parameter must match an IP address associated with the IP interface to which this LAG is bound. In addition, the remote-ip parameter must match an IP address on the remote system, and should also be in the same subnet as the local IP address. If the LAG bundle is reassociated with a different IP interface, the local-ip and remote-ip parameters should be modified to match the new IP subnet.