Dell PowerEdge FN I/O Module Configuration Guide 9.10(0.0)

To verify that STP is enabled, use the show config command from PROTOCOL SPANNING TREE mode.

Example of Verifying Spanning Tree is Enabled

Dell(conf)#protocol spanning-tree 0
                                 Dell(conf-span)#show config
                                 !
                                 protocol spanning-tree 0
                                 
                                 no disable
                                 Dell#
                              

To view the spanning tree configuration and the interfaces that are participating in STP, use the show spanning-tree 0 command from EXEC privilege mode. If a physical interface is part of a port channel, only the port channel is listed in the command output.

Example of Viewing Spanning Tree Configuration

R2#show spanning-tree 0
                                 Executing IEEE compatible Spanning Tree Protocol
                                 Bridge Identifier has priority 32768, address 0001.e826.ddb7
                                 Configured hello time 2, max age 20, forward delay 15
                                 Current root has priority 32768, address 0001.e80d.2462
                                 Root Port is 289 (GigabitEthernet 2/1), cost of root path is 4
                                 Topology change flag not set, detected flag not set
                                 Number of topology changes 3 last change occurred 0:16:11 ago
                                 from GigabitEthernet 2/3
                                 Timers: hold 1, topology change 35
                                 hello 2, max age 20, forward delay 15
                                 Times: hello 0, topology change 0, notification 0, aging Normal
                                 
                                 Port 289 (GigabitEthernet 2/1) is Forwarding
                                 Port path cost 4, Port priority 8, Port Identifier 8.289
                                 Designated root has priority 32768, address 0001.e80d.2462
                                 Designated bridge has priority 32768, address 0001.e80d.2462
                                 Designated port id is 8.496, designated path cost 0
                                 Timers: message age 1, forward delay 0, hold 0
                                 Number of transitions to forwarding state 1
                                 BPDU: sent 21, received 486
                                 The port is not in the portfast mode
                                 
                                 Port 290 (GigabitEthernet 2/2) is Blocking
                                 Port path cost 4, Port priority 8, Port Identifier 8.290
                                 --More--
                                 Timers: message age 1, forward delay 0, hold 0
                                 Number of transitions to forwarding state 1
                                 BPDU: sent 21, received 486
                                 The port is not in the portfast mode
                              

To confirm that a port is participating in Spanning Tree, use the show spanning-tree 0 brief command from EXEC privilege mode.

Example of Verifying a Port Participates in Spanning Tree

Dell#show spanning-tree 0 brief
                                 Executing IEEE compatible Spanning Tree Protocol
                                 Root ID Priority 32768, Address 0001.e80d.2462
                                 We are the root of the spanning tree
                                 Root Bridge hello time 2, max age 20, forward delay 15
                                 Bridge ID Priority 32768, Address 0001.e80d.2462
                                 Configured hello time 2, max age 20, forward delay 15
                                 Interface                          Designated
                                 Name    PortID Prio Cost Sts Cost  Bridge ID             PortID
                                 -------------- ------ ---- ---- --- ----- --------------------
                                 Tengig 1/1  8.496  8     4 DIS   0     32768 0001.e80d.2462  8.496
                                 Tengig 1/2  8.497  8     4 DIS   0     32768 0001.e80d.2462  8.497
                                 Tengig 1/3  8.513  8     4 FWD   0     32768 0001.e80d.2462  8.513
                                 Tengig 1/4  8.514  8     4 FWD   0     32768 0001.e80d.2462  8.514
                                 Dell#