Spanning-Tree Mst Max-Hops - Cisco Catalyst 3750 Command Reference Manual

Chapter 2 Catalyst 3750 Switch Cisco IOS Commands

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.
Syntax Description hop-count
Defaults
The default is 20 hops.
Command Modes Global configuration
Command History Release
12.1(14)EA1
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 Command
show spanning-tree
spanning-tree mst forward-time
spanning-tree mst hello-time
spanning-tree mst max-age
78-16181-03
spanning-tree mst max-hops hop-count
no spanning-tree mst max-hops
Number of hops in a region before the BPDU is discarded. The range is 1 to 40 hops.
Modification
This command was introduced.
mst
Description
Displays MST information.
Sets the forward-delay time for all MST instances.
Sets the interval between hello BPDUs sent by root switch
configuration messages.
Sets the interval between messages that the spanning tree
receives from the root switch.
Catalyst 3750 Switch Command Reference
spanning-tree mst max-hops
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