Cisco 2950G 24 Software Configuration Guide - Page 303

Chapter 12 Configuring RSTP and MSTP Configuring RSTP and MSTP Features Specifying the MST Region Configuration and Enabling MSTP For two or more switches to be in the same MST region, they must have the same VLAN-to-instance mapping, the same configuration revision number, and the same name. A region can have one member or multiple members with the same MST configuration; each member must be capable of processing RSTP BPDUs. There is no limit to the number of MST regions in a network, but each region can support up to 16 spanning-tree instances. You can assign a VLAN to only one spanning-tree instance at a time. Beginning in privileged EXEC mode, follow these steps to specify the MST region configuration and enable MSTP. This procedure is required. Step 1 Step 2 Step 3 Command configure terminal spanning-tree mst configuration instance instance-id vlan vlan-range Step 4 name name Step 5 Step 6 Step 7 Step 8 revision version show pending exit spanning-tree mode mst Purpose Enter global configuration mode. Enter MST configuration mode. Map VLANs to an MST instance. • For instance-id, the range is 1 to 15. • For vlan vlan-range, the range is 1 to 4094. When you map VLANs to an MST instance, the mapping is incremental, and the range of VLANs specified is added or removed to the existing ones. To specify a range, use a hyphen; for example, instance 1 vlan 1-63 maps VLANs 1 through 63 to MST instance 1. To specify a series, use a comma; for example, instance 1 vlan 10, 20, 30 maps VLANs 10, 20, and 30 to MST instance 1. Specify the configuration name. The name string has a maximum length of 32 characters and is case sensitive. Specify the configuration revision number. The range is 0 to 65535. Verify your configuration by displaying the pending configuration. Apply all changes, and return to global configuration mode. Enable MSTP. RSTP is also enabled. Step 9 Step 10 Step 11 end show running-config copy running-config startup-config Caution Changing spanning-tree modes can disrupt traffic because all spanning-tree instances are stopped for the previous mode and restarted in the new mode. You cannot run both MSTP and PVST at the same time. Return to privileged EXEC mode. Verify your entries. (Optional) Save your entries in the configuration file. To return to the default MST region configuration, use the no spanning-tree mst configuration global configuration command. To return to the default VLAN-to-instance map, use the no instance instance-id [vlan vlan-range] MST configuration command. To return to the default name, use the no name MST 78-14982-01 Catalyst 2950 Desktop Switch Software Configuration Guide 12-13