3-tier design/STPconfig
From Teknologisk videncenter
								
												
				Configure Switch 1 to be primary
DLS1(config)#<input>spanning-tree vlan 10 root primary</input> 
DLS1(config)#<input>end</input>
DLS1#<input>show spanning-tree vlan 10</input>
VLAN0010
  Spanning tree enabled <notice>protocol ieee</notice>
  <notice>Root ID    Priority    24586</notice>
             Address     0001.436B.E384
             <notice>This bridge is the root</notice>
             Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
  Bridge ID  Priority    24586  (priority 24576 sys-id-ext 10)
             Address     0001.436B.E384
             Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  20
Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/2            <notice>Desg FWD</notice> 19        128.2    P2p
DLS1#And Switch 2 to be secondary
DLS2(config)#<input>spanning-tree vlan 10 root secondary</input> 
DLS2(config)#