Reference Guide

3 Ensure the same region name is congured in all the bridges running MST.
4 (Optional) Congure the revision number.
Congure MST protocol
When you enable MST globally, all L2 physical, port-channel, and VLAN interfaces are automatically assigned to MST instance (MSTI) zero
(0). Within an MSTI, only one path from any one bridge to another is enabled for forwarding.
• Enable MST in CONFIGURATION mode.
spanning-tree mode mst
Congure and verify MSTP
OS10(config)# spanning-tree mode mst
OS10(config)# do show spanning-tree
show spanning-tree mst configuration
Region Name: ravi
Revision: 0
MSTI VID
0 1,7-4093
1 2
2 3
3 4
4 5
5 6
Add or remove interfaces
By default, all interfaces are enabled in L2 switchport mode, and all L2 interfaces are part of spanning-tree.
• Disable spanning-tree on an interface in INTERFACE mode.
spanning-tree disable
• Enable MST on an interface in INTERFACE mode.
no spanning-tree disable
Create instances
You can create multiple MSTP instances and map VLANs. A single MSTI provides no more benet than RSTP. To take full advantage of the
MST protocol, create multiple MSTIs and map VLANs to them.
1 Enter an instance number in CONFIGURATION mode.
spanning tree mst configuration
2 Enter the MST instance number in MULTIPLE-SPANNING-TREE mode (0 to 63).
instance instance-number
3 Enter the VLAN and IDs to participate in the MST instance in MULTIPLE-SPANNING-TREE mode (1 to 4096).
instance vlan-id
Create MST instances
OS10(config)# spanning-tree mst configuration
OS10(conf-mst)# name force10
OS10(conf-mst)# revision 100
OS10(conf-mst)# instance 1 vlan 2-10
OS10(conf-mst)# instance 2 vlan 11-20
OS10(conf-mst)# instance 3 vlan 21-30
Layer 2
195