Reference Guide

● 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 benefit than RSTP. To take full
advantage of the MSTP, 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
View VLAN instance mapping
OS10# show spanning-tree mst configuration
Region Name: force10
Revision: 100
MSTI VID
0 1,31-4093
1 2-10
2 11-20
3 21-30
View port forwarding/discarding state
OS10# show spanning-tree msti 0 brief
Spanning tree enabled protocol msti with force-version mst
MSTI 0 VLANs mapped 1,31-4093
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 32768, Address 3417.4455.667f
Root Bridge hello time 2, max age 20, forward delay 15, max hops 20
Bridge ID Priority 32768, Address 90b1.1cf4.a523
Configured hello time 2, max age 20, forward delay 15, max hops 20
CIST regional root ID Priority 32768, Address 90b1.1cf4.a523
CIST external path cost 500
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
-----------------------------------------------------------------------------------
ethernet1/1/1 128.260 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.260
ethernet1/1/2 128.264 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.264
ethernet1/1/3 128.268 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.268
ethernet1/1/4 128.272 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.272
ethernet1/1/5 128.276 128 500 FWD 0 32768 3417.4455.667f 128.146
ethernet1/1/6 128.280 128 500 BLK 0 32768 3417.4455.667f 128.150
ethernet1/1/7 128.284 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.284
ethernet1/1/8 128.288 128 200000000 BLK 0 32768 90b1.1cf4.a523 128.288
Layer 2
197