Configuring the Spanning Tree Protocol

The Spanning Tree Protocol is used only when single-route explorer frames are used for route discovery. Novell's default end station implementation originates a route discovery session by issuing a single-route explorer frame. When a bridge sends out a single-route explorer frame, it travels over a single route that is manually configured or automatically determined by the Spanning Tree Protocol.

The automatic mode provides the most efficient and dynamic way to determine a single route, because bridge interfaces reconfigure themselves automatically when other bridges fail. By configuring source route bridge interfaces in this way, they can automatically take advantage of the best available single route as other bridges go down or come up.

If you configure your network manually, you must ensure that there are no loops in the topology and that there is only one single-route path to any particular ring. Also, at least one single-route path must be configured for each ring to maintain connectivity. However, by carefully configuring the bridge interfaces in the network, you can create preferred routes for route determination, freeing rings whose operation is most sensitive from most explorer frame traffic.

By definition, a single-route explorer frame travels a single route to the destination. A forwarding interface passes all-routes explorer frames, single-route explorer frames, and specifically routed frames. A blocking interface passes all-routes explorer frames and specifically routed frames.

We strongly recommend that you use the Spanning Tree Protocol to configure your bridge interfaces automatically. For more information about the Spanning Tree Protocol, refer to Understanding.

How to Configure the Spanning Tree Protocol

Before you begin, you must configure one of the source route bridge application scenarios described in this section.

To configure the Spanning Tree Protocol, complete the following steps:

Load NIASCFG and configure the Spanning Tree Protocol for each source route bridge as follows:

Select the following parameter path:

Select Bindings > an existing binding to a source route bridged interface

From the Binding Source Route Bridge to an Interface menu, configure the Spanning Tree Mode parameter by selecting one of the following modes:

Select Automatic to configure your bridge interfaces automatically. This is the recommended and default setting.

Select Manual (Block) to disable the forwarding of single-route explorer frames.

Select Manual (Forward) to enable the forwarding of single-route explorer frames.

Select No Bridging to disable bridging between an interface and other interfaces. This is relevant only when the SRBRIDGE driver is loaded.

Press Esc to return to the Internetworking Configuration menu; save your changes when prompted.

If you want these changes to take effect immediately, restart the router.

If you want to configure other parameters, do so now, then restart the router when you are finished.