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10. CLI COMMANDS: SWITCHING
10.1 Spanning Tree Commands
This section provides detailed explanation of the spanning tree commands. The commands are divided
into two functional groups:
▫
Show commands
display spanning tree settings, statistics, and other information.
▫
Configuration Commands
configure features and options of the switch. For every configuration
command there is a show command that displays the configuration setting.
10.1.1 show spanning-tree
This command displays spanning tree settings for the common and internal spanning tree, when the
optional parameter "brief" is not included in the command. The following details are displayed.
▫
Format show spanning-tree [brief]
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Mode
Privileged EXEC and User EXEC
▫
Bridge Priority -
Configured value.
▫
Bridge Identifier
▫
Time Since Topology Change -
in seconds
▫
Topology Change Count -
Number of times changed.
▫
Topology Change -
Boolean value of the Topology Change parameter for the switch indicating if a
topology change is in progress on any port assigned to the common and internal spanning tree.
▫
Designated Root
▫
Root Path Cost -
Value of the Root Path Cost parameter for the common and internal spanning
tree.
▫
Root Port Identifier
▫
Root Port Max Age -
Derived value
▫
Root Port Bridge Forward Delay -
Derived value
▫
Hello Time -
Configured value
▫
Bridge Hold Time - Minimum time between transmission of Configuration Bridge Protocol Data
Units (BPDUs)
▫
CST Regional Root
▫
Regional Root Path Cost
▫
Associated FIDs -
List of forwarding database identifiers currently associated with this instance.
▫
Associated VLANs -
List of VLAN IDs currently associated with this instance.
When the "brief" optional parameter is included, this command displays spanning tree settings for the
bridge. In this case, the following details are displayed.
▫
Bridge Priority
- Configured value.