S1交换机：

set protocols stp enable                              #"打开stp功能"

set protocols stp bridge-priority 8k                  #"设置stp的优优先值"

set protocols stp interface ge-0/0/1.0 priority 8     #"设置stp端口优先值"

set protocols stp interface ge-0/0/2.0 priority 8

S2交换机：

set protocols stp enable

set protocols stp bridge-priority 16k

set protocols stp interface ge-0/0/1.0 priority 16

set protocols stp interface ge-0/0/2.0 priority 16

S3交换机：

set protocols stp enable

set protocols stp bridge-priority 32k

set protocols stp interface ge-0/0/1.0 priority 32

set protocols stp interface ge-0/0/2.0 priority 32

检查命令：

Show span-tree bridge

转载自：http://mtonet.com/?p=282