Specifications

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Cisco ME 3400 Ethernet Access Switch Command Reference
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Chapter 2 Cisco ME 3400 Ethernet Access Switch Cisco IOS Commands
spanning-tree mst max-age
spanning-tree mst max-age
Use the spanning-tree mst max-age global configuration command 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.
spanning-tree mst max-age seconds
no spanning-tree mst max-age
Syntax Description
Defaults The default is 20 seconds.
Command Modes Global configuration
Command History
Usage Guidelines On the Cisco ME switch, spanning-tree MST configuration is supported only on network node interfaces
(NNIs) or on enhanced network interfaces (ENIs) on which Spanning Tree Protocol (STP) has been
enabled. To set a port as an NNI or ENI, enter the port-type {eni | nni} interface configuration
command. To enable STP on an ENI, enter the spanning-tree interface configuration command.
User network interfaces (UNIs) do not participate in STP.
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.
seconds Interval between messages the spanning tree receives from the root switch. The range is
6 to 40 seconds.
Release Modification
12.2(25)EX This command was introduced.