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Catalyst 3750-X and 3560-X Switch Command Reference
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Chapter 2 Catalyst 3750-X and 3560-X Switch Cisco IOS Commands
spanning-tree mst max-hops
spanning-tree mst max-hops
Use the spanning-tree mst max-hops global configuration command on the switch stack or on a
standalone switch to set the number of hops in a region before the bridge protocol data unit (BPDU) is
discarded and the information held for an interface is aged. Use the no form of this command to return
to the default setting.
spanning-tree mst max-hops hop-count
no spanning-tree mst max-hops
Syntax Description
Defaults The default is 20 hops.
Command Modes Global configuration
Command History
Usage Guidelines The root switch of the instance always sends a BPDU (or M-record) with a cost of 0 and the hop count
set to the maximum value. When a switch receives this BPDU, it decrements the received remaining hop
count by one and propagates the decremented count as the remaining hop count in the generated
M-records. A switch discards the BPDU and ages the information held for the interface when the count
reaches 0.
Changing the spanning-tree mst max-hops command affects all spanning-tree instances.
Examples This example shows how to set the spanning-tree max-hops to 10 for all multiple spanning-tree (MST)
instances:
Switch(config)# spanning-tree mst max-hops 10
You can verify your setting by entering the show spanning-tree mst privileged EXEC command.
Related Commands
hop-count Number of hops in a region before the BPDU is discarded. The range is 1 to 255 hops.
Release Modification
12.2(53)SE2 This command was introduced.
Command Description
show spanning-tree mst Displays MST information.
spanning-tree mst forward-time Sets the forward-delay time for all MST instances.
spanning-tree mst hello-time Sets the interval between hello BPDUs sent by root switch
configuration messages.
spanning-tree mst max-age Sets the interval between messages that the spanning tree
receives from the root switch.