29.7.11 Configuration in which both ring ports of the master node are shared links

In a multi-ring configuration shown in the figure below, both ring ports of the master node (switch 3 of ring 1) are shared links. In such a configuration, set the master node of a shared link non-monitoring ring (switch 1 of ring 2) to send flush control frames for neighboring rings using the flush-request-transmit vlan configuration command.

If a ring fault occurs in a shared link non-monitoring ring with this configuration, the master nodes can switch to a new communication path by sending flush control frames for neighboring rings to neighboring devices in the ring. The same applies to the case where a shared link non-monitoring ring is recovered from a fault.

Figure 29-48: Configuration example in which both ring ports of a master node are shared links

If you do not configure the settings to send flush control frames for neighboring rings in this configuration and a ring fault occurs in a shared link non-monitoring ring, the path is switched in the shared link non-monitoring ring but is not switched in neighboring shared link monitoring rings. As a result, old MAC address learning data is left on devices in the shared link monitoring rings and it may take some time to switch the communication path. The same applies to the case where a shared link non-monitoring ring is recovered from a fault.