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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 21 Configuring MSTP
How to Configure MSTP
Step 4 spanning-tree mst forward-time seconds Configures the forward time for all MST instances. The
forward delay is the number of seconds a port waits before
changing from its spanning-tree learning and listening states
to the forwarding state.
seconds—The range is 4 to 30; the default is 15.
Step 5 spanning-tree mst max-age seconds Configures the maximum-aging time for all MST instances.
The maximum-aging time is the number of seconds a switch
waits without receiving spanning-tree configuration
messages before attempting a reconfiguration.
seconds—The range is 6 to 40; the default is 20.
Step 6 spanning-tree mst max-hops hop-count Specifies the number of hops in a region before the BPDU is
discarded, and the information held for a port is aged.
hop-count—The range is 1 to 255; the default is 20.
Step 7 interface interface-id Specifies an interface to configure, and enters interface
configuration mode.
Valid interfaces include physical ports and port-channel
logical interfaces.
Step 8 spanning-tree mst instance-id port-priority
priority
Configures the port priority.
instance-id—Specifies a single instance, a range of
instances separated by a hyphen, or a series of instances
separated by a comma. The range is 0 to 4096.
priority—The range is 0 to 240 in increments of 16. The
default is 128. The lower the number, the higher the
priority.
The priority values are 0, 16, 32, 48, 64, 80, 96, 112, 128,
144, 160, 176, 192, 208, 224, and 240. All other values
are rejected.
Step 9 spanning-tree mst instance-id cost cost Configures the cost.
If a loop occurs, the MSTP uses the path cost when selecting
an interface to place into the forwarding state. A lower path
cost represents higher-speed transmission.
instance-id—Specifies a single instance, a range of
instances separated by a hyphen, or a series of instances
separated by a comma. The range is 0 to 4096.
cost—The range is 1 to 200000000; the default value is
derived from the media speed of the interface.
Step 10 spanning-tree link-type point-to-point Specifies that the link type of a port is point-to-point.
Step 11 spanning-tree mst pre-standard Specifies that the port can send only prestandard BPDUs.
Step 12 end Returns to privileged EXEC mode.
Command Purpose