Spanning-Tree Mst Configuration - Cisco Catalyst 2960-X Command Reference Manual

spanning-tree mst configuration

spanning-tree mst configuration
To enter MST-configuration mode, use the spanning-tree mst configuration command in global configuration
mode. To return to the default settings, use the no form of this command.
spanning-tree mst configuration
no spanning-tree mst configuration
Syntax Description
This command has no arguments or keywords.
Command Default
The default value for the Multiple Spanning Tree (MST) configuration is the default value for all its parameters:
• No VLANs are mapped to any MST instance (all VLANs are mapped to the Common and Internal
• The region name is an empty string.
• The revision number is 0.
Command Modes
Global configuration
Command History
Release
Cisco IOS 15.0(2)EX
Usage Guidelines
In MST mode, a switch stack supports up to 65 MST instances. The number of VLANs that can be mapped
to a particular MST instance is unlimited.
For two or more switches to be in the same MST region, they must have the same VLAN mapping, the same
configuration name, and the same configuration revision number.
When you map VLANs to an MST instance, the mapping is incremental, and VLANs specified in the command
are added to or removed from the VLANs that were previously mapped. To specify a range, use a hyphen;
for example, instance 1 vlan 1-63 maps VLANs 1 to 63 to MST instance 1. To specify a series, use a comma;
for example, instance 1 vlan 10, 20, 30 maps VLANs 10, 20, and 30 to MST instance 1.
All VLANs that are not explicitly mapped to an MST instance are mapped to the common and internal spanning
tree (CIST) instance (instance 0) and cannot be unmapped from the CIST by using the no form of this command.
Changing an MST-configuration mode parameter can cause connectivity loss. To reduce service disruptions,
when you enter MST-configuration mode, make changes to a copy of the current MST configuration. When
you have finished editing the configuration, you can apply all the changes at once by using the exit keyword,
or you can exit the mode without committing any change to the configuration by using the abort keyword.
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
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Spanning Tree [CIST] instance).
Modification
This command was introduced.
Layer 2 Commands
OL-29043 -01