HP 6125G HP 6125G & 6125G/XG Blade Switches High Availability Configur - Page 113

Configuring Monitor Link Monitor Link overview Monitor Link is a port collaboration function. Monitor Link usually works together with Layer 2 topology protocols. The idea is to monitor the states of uplink ports and adapt the up/down state of downlink ports to the up/down state of uplink ports, triggering link switchover on the downstream device in time, as shown in Figure 25. Figure 25 Monitor Link application scenario Port1 Port1 Port2 Port1 Port2 Port1 Port2 Port2 Terminology Monitor link group A monitor link group is a set of uplink and downlink ports. A port can belong to only one monitor link group. As shown in Figure 25, ports Port1 and Port2 of Device B and those of Device D each form a monitor link group. Port1 on both devices are uplink ports, and Port2 on both devices are downlink ports. Uplink/Downlink ports Uplink port and downlink port are two port roles in monitor link groups: • Uplink ports are the monitored ports. The state of a monitor link group adapts to that of its member uplink ports. When a monitor link group contains no uplink port or when all the uplink ports are down, the monitor link group becomes down. As long as one member uplink port is up, the monitor link group stays up. 106