show spantree

Use the show spantree command to display spanning-tree information for a VLAN.

show spantree [vlan | mod_num/port_num] [active | backbonefast | blockedports | portstate | statistics | summary]

Syntax Description

vlan	(Optional) Number of the VLAN. If the VLAN number is not specified, the default is VLAN 1.
mod_num	(Optional) Number of the module.
port_num	(Optional) Number of the port on the module.
active	(Optional) Keyword used to display only the active ports.
backbonefast	(Optional) Keyword used to show whether the Spanning-Tree Backbone Fast Convergence feature is enabled.
blockedports	(Optional) Keyword used to display only the blocked ports.
portstate	(Optional) Keyword used to display the port state.
statistics	(Optional) Keyword used to display spantree statistics.
summary	(Optional) Keyword used to display only summary information.

Default

This command has no default setting.

Command Type

Switch command.

Command Mode

Normal.

Example

This example shows how to display the Spanning-Tree configuration for VLAN 1005:

Console> show spantree 1005
VLAN 1005
Spanning tree enabled
 
Designated Root             00-40-0b-8f-8b-ec
Designated Root Priority    32768
Designated Root Cost        0
Designated Root Port        1/0
Root Max Age   6  sec    Hello Time 2  sec   Forward Delay 4  sec
 
Bridge ID MAC ADDR          00-40-0b-8f-8b-ec
Bridge ID Priority          32768
Bridge Max Age 6  sec    Hello Time 2  sec   Forward Delay 4  sec
 
Port,Vlan Vlan  Port-State     Cost   Priority  Fast-Start  Group-method
--------- ----  -------------  -----  --------  ----------  ------------
 1003     1005  inactive          80        32   disabled
Console>
  

Table 6-35 describes the fields in the show spantree command output when issued against a TrBRF.
Table  6-35: show spantree Command Output Fields

Field	Description
VLAN	VLAN for which spanning-tree information is shown.
Spanning tree	Status of whether Spanning-Tree Protocol is enabled or disabled.
Designated Root	MAC address of the designated spanning-tree root bridge.
Designated Root Priority	Priority of the designated root bridge.
Designated Root Cost	Total path cost to reach the root.
Designated Root Port	Port through which the root bridge can be reached (shown only on nonroot bridges).
Root Max Age	Amount of time a BPDU1 packet should be considered valid.
Hello Time	Number of times the root bridge sends BPDUs.
Forward Delay	Amount of time the port spends in listening or learning mode.
Bridge ID MAC ADDR	Bridge MAC address.
Bridge ID Priority	Bridge priority.
Bridge Max Age	Bridge maximum age.
Hello Time	Amount of time the bridge sends BPDUs.
Forward Delay	Amount of time the bridge spends in listening or learning mode.
Port	Port number.
Vlan	VLAN to which the port belongs.
Port-State	Spanning-tree port state (disabled, inactive, not-connected, blocking, listening, learning, forwarding, bridging, type-pvid-inconsistent).
Cost	Cost associated with the port.
Priority	Priority associated with the port.
Fast-Start	Status of whether the port is configured to use the fast-start feature.