Dell Force10 S50P FTOS Configuration Guide FTOS 8.4.2.7 E-Series TeraScale, C- - Page 645

Enable Multiple Spanning Tree Globally MSTP is not enabled by default. To enable MSTP: Step 1 2 Task Enter PROTOCOL MSTP mode. Enable MSTP. Command Syntax protocol spanning-tree mstp no disable Command Mode CONFIGURATION PROTOCOL MSTP Verify that MSTP is enabled using the show config command from PROTOCOL MSTP mode, as shown in Figure 29-2. Figure 29-2. Verifying MSTP is Enabled FTOS(conf)#protocol spanning-tree mstp FTOS(config-mstp)#show config ! protocol spanning-tree mstp no disable FTOS# When you enable MSTP, all physical, VLAN, and port-channel interfaces that are enabled and in Layer 2 mode are automatically part of the MSTI 0. • Within an MSTI, only one path from any bridge to any other bridge is enabled. • Bridges block a redundant path by disabling one of the link ports. Add and Remove Interfaces • To add an interface to the MSTP topology, configure it for Layer 2 and add it to a VLAN. If you previously disabled MSTP on the interface using the command no spanning-tree 0, re-enable it using the command spanning-tree 0. • Remove an interface from the MSTP topology using the command no spanning-tree 0 command. See also Removing an Interface from the Spanning Tree Group on page 1054 for BPDU Filtering behavior. Create Multiple Spanning Tree Instances A single MSTI provides no more benefit than RSTP. To take full advantage of MSTP you must create multiple MSTIs and map VLANs to them. Create an MSTI using the command msti from PROTOCOL MSTP mode. Specify the keyword vlan followed by the VLANs that you want to participate in the MSTI, as shown in Figure 29-3. Multiple Spanning Tree Protocol | 645