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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 21 Configuring MSTP
How to Configure MSTP
Configuring the Root Switch
Before You Begin
After configuring the switch as the root switch, we recommend that you avoid manually configuring the
hello time, forward-delay time, and maximum-age time t hrough the spanning-tree mst hello-time,
spanning-tree mst forward-time, and the spanning-tree mst max-age global configuration
commands.
This task is optional.
Step 8 spanning-tree mode mst Enables MSTP. RSTP is also enabled.
Caution Changing spanning-tree modes can disrupt traffic because all
spanning-tree instances are stopped for the previous mode and
restarted in the new mode.
You cannot run both MSTP and PVST+ or both MSTP and rapid PVST+
at the same time.
Step 9 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 root primary
[diameter net-diameter [hello-time seconds]]
Configures a switch as the 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.