Spanning Tree

enable spanning tree

switch>enable 
switch#configure terminal 
Enter configuration commands, one per line. End with CNTL/Z.
switch(config)#spanning-tree vlan 1
switch(config)#end
switch#

disable spanning tree

switch(config)#no spanning-tree vlan 1

configure root bridge

switch(config)#spanning-tree vlan 1-4094 root primary

priority to 8192

switch(config)#spanning-tree vlan 1-4094 root secondary

priority to 16384