29.7.9 Prohibited Configuration of Ring Protocol

The following describes prohibited configurations for networks using the Ring Protocol.

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(1) Multiple master nodes in the same ring

Do not set multiple master nodes within the same ring. When the same ring contains multiple master nodes, because the secondary port is logically blocked, the network is cut, preventing proper communication.

Figure 29-42: Setting multiple master nodes in the same ring

(2) Configuration with multiple shared link monitoring rings

In a multi-ring configuration with shared links, make sure that there is only one shared link monitoring ring within the network. If the network contains multiple shared link monitoring rings, fault monitoring within the shared link non-monitoring ring gets cut, preventing proper fault monitoring.

Figure 29-43: Configuration with multiple shared link monitoring rings

(3) Example of Multiple Ring Configuration for Looping

For multi-ring configurations such as that in the following figure, loops form between transit nodes.

Figure 29-44: Multi-ring configuration for looping

(4) Configurations in which the primary port of the master node cannot be determined

Do not set a node located at one of the two terminal nodes of a shared link non-monitoring ring as the master node (shown in the figure below). In such configuration, the two ring ports of the master node will be shared links, and the primary port cannot be correctly determined.

Figure 29-45: Configuration in which the primary port of the master node cannot be determined