27.5.2 Checking the status of PVST +

PVST+ information is displayed in the execution results of the show spanning-tree command. The PVST+ or Rapid PVST+ operation mode can be checked in Mode. To check that the topology has been built properly, make sure that the contents of Root Bridge ID are correct, along with Status and Role in Port Information.

Figure 27-8: Result of executing show spanning-tree command
> show spanning-tree vlan 1 Date 20XX/09/04 11:39:43 UTC VLAN 1 PVST+ Spanning Tree:Enabled Mode:PVST+ Bridge ID Priority:32769 MAC Address:0012.e205.0900 Bridge Status:Designated Root Bridge ID Priority:32769 MAC Address:0012.e201.0900 Root Cost:1000 Root Port:1/0/1 Port Information 1/0/1 Up Status:Forwarding Role:Root 1/0/2 Up Status:Forwarding Role:Designated 1/0/3 Up Status:Blocking Role:Alternate 1/0/4 Down Status:Disabled Role:- 1/0/10 Up Status:Forwarding Role:Designated PortFast 1/0/11 Up Status:Forwarding Role:Designated PortFast 1/0/12 Up Status:Forwarding Role:Designated PortFast >

Figure 27-8: Result of executing show spanning-tree command

> show spanning-tree vlan 1
Date 20XX/09/04 11:39:43 UTC
VLAN 1              PVST+ Spanning Tree:Enabled  Mode:PVST+
  Bridge ID        Priority:32769       MAC Address:0012.e205.0900
    Bridge Status:Designated
  Root Bridge ID   Priority:32769       MAC Address:0012.e201.0900
    Root Cost:1000
    Root Port:1/0/1
  Port Information
    1/0/1      Up    Status:Forwarding  Role:Root                 
    1/0/2      Up    Status:Forwarding  Role:Designated           
    1/0/3      Up    Status:Blocking    Role:Alternate            
    1/0/4      Down  Status:Disabled    Role:-                    
    1/0/10     Up    Status:Forwarding  Role:Designated PortFast  
    1/0/11     Up    Status:Forwarding  Role:Designated PortFast  
    1/0/12     Up    Status:Forwarding  Role:Designated PortFast  
>