DELL S50V User Manual

Multiple Spanning Tree Protocol | 647

MSTP determines the root bridge, but you can assign one bridge a lower priority to increase the probability 
that it will become the root bridge.

To change the bridge priority:

than MSTI 2. View the bridge priority using the command 

 from PROTOCOL MSTP mode, 

FTOS supports only one MSTP region. A region is a combination of three unique qualities:

•

Name is a mnemonic string you assign to the region. The default region name on FTOS is null.

•

Revision is a two-byte number. The default revision number on FTOS is 0.

•

VLAN-to-instance mapping is the placement of a VLAN in an MSTI.

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 will match on all Dell Force10 FTOS equipment. If you have 
non-FTOS equipment that will participate in MSTP, ensure these values to match on all the equipment.

Assign a number as the bridge priority. A lower number 
increases the probability that the bridge becomes the root 
bridge.
Range: 0-61440, in increments of 4096
Default: 32768

 

 

PROTOCOL MSTP

Note: Some non-FTOS equipment may implement a non-null default region name. SFTOS, for example, 
uses the Bridge ID, while others may use a MAC address.

R3(conf-mstp)#

msti 2 bridge-priority 0

1d2h51m: %RPM0-P:RP2 %SPANMGR-5-STP_ROOT_CHANGE: MSTP root changed for instance 2. My 

Bridge ID: 0:0001.e809.c24a Old Root: 32768:0001.e806.953e 

New Root: 0:0001.e809.c24a

R3(conf-mstp)#show config

!

protocol spanning-tree mstp

 no disable

 MSTI 1 VLAN 100

 MSTI 2 VLAN 200,300

 MSTI 2 bridge-priority 0