Dell EMC SmartFabric OS10 User Guide Release 10.5.0

MSTP 根据最小桥 ID 确定根桥。要增加桥被选为根桥的可能性，请为该桥分配较低的桥优先级数值。

您可以设置优先级值 0 以强制交换机成为根交换机。值 0 为最高优先级。

• 在 CONFIGURATION 模式下为特定实例分配桥优先级编号，从 0 到 61440，增量为 4096，默认值为 32768。

  spanning-tree mst instance-number priority priority

分配根桥优先级

OS10(config)# spanning-tree mst 0 priority 32768

OS10# show spanning-tree active
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
---------------------------------------------------------------------------
ethernet1/1/5  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
Interface
Name           Role PortID   Prio Cost Sts  Cost Link-type Edge
--------------------------------------------------------------
ethernet1/1/5  Root 128.276  128  500  FWD  0    AUTO      No
ethernet1/1/6  Altr 128.280  128  500  BLK  0    AUTO      No