152 | Spanning Treew w w . d e l l . c o m | s u p p o r t . d e l l . c o m Enabling STPUse the following commands to run Spanning Tree convergence on participating switches.Example of configuring STPFigure 10-110 shows three S-Series switches, S50-1, S50-2, and S50-3. A physical connection existsbetween each pair of switches. Enabling the Spanning Tree Protocol (STP) on this topology will enableone least-cost route between each of the switches, so that redundant packets are not sent in both directionsaround the loop.Figure 10-110. Spanning Tree Topology Example1. Use the show spanning-tree interface command and show spanning-tree summary command todetermine if STP is initially disabled on the interface and globally (See Figure 10-116 on page 158 andExample Output from show spanning-tree vlan Command on page 162). Use show spanning-tree brief(see Figure 10-118 on page 159) to determine the current bridge characteristics.2. In Global Config mode on each participating switch, use the spanning-tree command to enableSpanning Tree.spanning tree Global Config Enable the Spanning Tree Protocol on participatingswitches.spanning-tree port mode enable Interface Config Enable STP on selected ports.spanning-tree port mode enable all Global Config Alternatively to enabling STP on selected ports,activate STP on all ports.spanning-tree port mode enable all Interface PortChannel ConfigEnable STP on participating LAGs.S50-1 S50-2S50-31/0/11/0/21/0/11/0/21/0/2 1/0/1
