Lab 24 Spanning Tree

Objective

• To understand spanning tree protocol11

Topology

Basic Setting

This is a LAN for a building, and two distribution layer switches are used for redundancy.

Requirements

• Check current root bridge
• Manually assign root switch.

Steps

On Switch10

Switch#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
   Address 0002.4A63.C9B6
   This bridge is the root
   Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
   Address 0002.4A63.C9B6
   Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
   Aging Time 20
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/1 Desg FWD 19 128.1 P2p
Fa1/1 Desg FWD 19 128.2 P2p
Fa2/1 Desg FWD 19 128.3 P2p
Gi5/1 Desg FWD 4 128.6 P2p
Gi6/1 Desg FWD 4 128.7 P2p
Gi7/1 Desg FWD 4 128.8 P2p
Gi8/1 Desg FWD 4 128.9 P2p
Switch#

On Switch11

Switch(config)#spanning-tree vlan 1 priority 4096

Check network status again

On Switch11

Switch#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 4097
     Address 00E0.F780.208C
     This bridge is the root
     Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 4097 (priority 4096 sys-id-ext 1)
     Address 00E0.F780.208C
     Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
     Aging Time 20
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi8/1 Desg FWD 4 128.9 P2p
Gi7/1 Desg FWD 4 128.8 P2p
Gi6/1 Desg FWD 4 128.7 P2p
Gi5/1 Desg FWD 4 128.6 P2p
Switch#