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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 21 Configuring MSTP
How to Configure MSTP
Configuring the Optional MSTP Parameters
Before You Begin
Exercise care when configuring the switch priority. For most situations, we recommend that you use the
spanning-tree mst instance-id root primary and the spanning-tree mst instance-id root secondary
global configuration commands to modify the switch prior ity.
Step 3 spanning-tree mst instance-id root secondary
[diameter net-diameter [hello-time seconds]]
Configures a switch as the secondary root switch.
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.
(Optional) diameter net-diameter—Specifies the
maximum number of switches between any two end
stations. The range is 2 to 7. This keyword is available
only for MST instance 0.
(Optional) hello-time seconds—Specifies the interval in
seconds between the generation of configuration messages
by the root switch. The range is 1 to 10 seconds; the
default is 2 seconds.
Use the same network diameter and hello-time values that you
used when configuring the primary root switch.
Step 4 end Returns to privileged EXEC mode.
Command Purpose
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 spanning-tree mst instance-id priority priority Configures the switch 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 61440 in increments of 4096;
the default is 32768. The lower the number, the more
likely the switch will be chosen as the root switch.
Priority values are 0, 4096, 8192, 12288, 16384, 20480,
24576, 28672, 32768, 36864, 40960, 45056, 49152,
53248, 57344, and 61440. All other values are rejected.
Step 3 spanning-tree mst hello-time seconds Configures the hello time for all MST instances. The hello
time is the interval between the generation of configuration
messages by the root switch. These messages mean that the
switch is alive.
seconds—The range is 1 to 10; the default is 2.