Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
spanning-tree mst max-age
Use the spanning-tree mst max-age global configuration command on the switch stack or on a
standalone switch to set the interval between messages that the spanning tree receives from the root
switch. If a switch does not receive a bridge protocol data unit (BPDU) message from the root switch
within this interval, it recomputes the spanning-tree topology. Use the no form of this command to return
to the default setting.
Syntax Description
seconds
Defaults
The default is 20 seconds.
Command Modes
Global configuration
Command History
Release
12.1(14)EA1
Usage Guidelines
After you set the spanning-tree mst max-age seconds global configuration command, if a switch does
not receive BPDUs from the root switch within the specified interval, the switch recomputes the
spanning-tree topology. The max-age setting must be greater than the hello-time setting.
Changing the spanning-tree mst max-age command affects all spanning-tree instances.
Examples
This example shows how to set the spanning-tree max-age to 30 seconds for all multiple spanning-tree
(MST) instances:
Switch(config)# spanning-tree mst max-age 30
You can verify your setting by entering the show spanning-tree mst privileged EXEC command.
78-16181-01
spanning-tree mst max-age seconds
no spanning-tree mst max-age
Interval between messages the spanning tree receives from the root switch. The range is
6 to 40 seconds.
Modification
This command was introduced.
spanning-tree mst max-age
Catalyst 3750 Switch Command Reference
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