Administrator Guide

For a bridge to be in the same MSTP region as another, all three of these qualities must match exactly. The
default values for name and revision match on all Dell Networking OS equipment. If you have non-Dell
Networking OS equipment that participates in MSTP, ensure these values match on all the equipment.
NOTE: Some non-Dell Networking OS equipment may implement a non-null default region name.
SFTOS, for example, uses the Bridge ID, while others may use a MAC address.
Changing the Region Name or Revision
To change the region name or revision, use the following commands.
• Change the region name.
PROTOCOL MSTP mode
name name
• Change the region revision number.
PROTOCOL MSTP mode
revision number
The range is from 0 to 65535.
The default is 0.
Example of the name Command
To view the current region name and revision, use the show spanning-tree mst configuration
command from EXEC Privilege mode.
Dell(conf-mstp)#name my-mstp-region
Dell(conf-mstp)#exit
Dell(conf)#do show spanning-tree mst config
MST region name: my-mstp-region
Revision: 0
MSTI VID
1 100
2 200-300
Modifying Global Parameters
The root bridge sets the values for forward-delay, hello-time, max-age, and max-hops and overwrites the
values set on other MSTP bridges.
• Forward-delay — the amount of time an interface waits in the Listening state and the Learning state
before it transitions to the Forwarding state.
• Hello-time — the time interval in which the bridge sends MSTP bridge protocol data units (BPDUs).
• Max-age — the length of time the bridge maintains configuration information before it refreshes that
information by recomputing the MST topology.
• Max-hops — the maximum number of hops a BPDU can travel before a receiving switch discards it.
Multiple Spanning Tree Protocol (MSTP) 609