Collaboration between Smart Link and Track for link status detection

Smart Link cannot detect unidirectional links, misconnected fibers, or packet loss on intermediate devices or network paths of the uplink. It cannot detect when faults are cleared either. To detect link status, smart link group member ports must use link detection protocols. When a fault is detected or cleared, the link detection protocols inform Smart Link to switch over the links.

Smart Link collaborates with link detection protocols through track entries. It supports only the Continuity Check (CC) function of Connectivity Fault Detection (CFD) to implement link detection. CFD notifies the smart link group member ports of fault detection events by using detection VLANs and detection ports. A port responds to a continuity check event only when the control VLAN of the smart link group to which it belongs matches the detection VLAN. For more information about track entries and the CC function of CFD, see "Configuring Track" and "Configuring CFD."