Cisco ME 3600X, Command Reference Manual

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Cisco ME 3800X and ME 3600X Switch Command Reference
OL-28238-01
Chapter
spanning-tree mst max-hops
spanning-tree mst max-hops
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
spanning-tree mst max-hops command in global
configuration mode. To return to the default setting, use the no form of this command.
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.
You can verify your setting by entering the show spanning-tree mst privileged EXEC command.
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
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(52)EY 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.