CCNA LAB Practice - Spanning Tree Protocol On 1900 Switch

Spanning Tree Protocol

On

1900 Switch

                                

Objective

Understanding the Spanning tree protocol operation in switched environment by creating a multiple or redundant link between switches.

Diagram With Redundant Link

Procedure

1. Verifying the Spanning Tree Protocol on the 1900-SWA switch.
2. Verifying the Spanning Tree Protocol on the 1900-SWB switch.
3. Select Root Port By Changing Priority Of Ports On 1900-SWA (Root Switch).
4. Verifying the results by changing Priority of ports on 1900-SWA & 1900-SWB.
5. Change 1900-SWB (Non-Root Switch) to Root Switch.
6. Verifying the results on 1900-SWA & 1900-SWB.
7. Select Root Port By Changing Cost Of Ports On 1900-SWANon-Root Switch).
8. Verifying the results by changing cost on 1900-SWA

Configuration         

Step 1(A): Verifying the Spanning Tree Protocol on the 1900-SWA Switch.

1900-SWA#show spantree

 

OR

1900-SWA#show spantree 1

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0003.6B33.42C0

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 32768, address 0003.6B33.42C0

   Root port is N/A, cost of root path is 0

   Topology change flag not set, detected flag not set

   Topology changes 1, last topology change occured 0d00h12m04s ago

   Times:  hold 1, topology change 8960

           hello 2, max age 20, forward delay 15

   Timers: hello 2, topology change 35, notification 2

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Forwarding

   Port path cost 9, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 1(B): Verifying the information of Spanning Tree Protocol on the

                        FastEthernet0/26 interface of 1900-SWA Switch.

1900-SWA#show interfaces fastEthernet 0/26

FastEthernet 0/26 is Enabled

Hardware is Built-in 100Base-TX

Address is 0003.6B33.42DA

MTU 1500 bytes, BW 100000 Kbits

802.1d STP State:  Forwarding     Forward Transitions:  1

Port monitoring: Disabled

Unknown unicast flooding: Enabled

Unregistered multicast flooding: Enabled

Description:

Duplex/Flow Control setting: Auto-negotiate

Auto-negotiation status:  Full duplex

Enhanced Congestion Control: Disabled

<Output Omitted>

Step 1(C): Verifying the information of Spanning Tree Protocol on the

                        FastEthernet0/27 interface of 1900-SWA Switch.

1900-SWA#show interfaces fastEthernet 0/27

FastEthernet 0/27 is Enabled

Hardware is Built-in 100Base-TX

Address is 0003.6B33.42DB

MTU 1500 bytes, BW 100000 Kbits

802.1d STP State:  Forwarding     Forward Transitions:  1

Port monitoring: Disabled

Unknown unicast flooding: Enabled

Unregistered multicast flooding: Enabled

Description:

Duplex/Flow Control setting: Auto-negotiate

Auto-negotiation status:  Full duplex

Enhanced Congestion Control: Disabled

<Output Omitted>

Step 2(A): Verifying the Spanning Tree Protocol on the 1900-SWB Switch.

1900-SWB#show spantree

OR

1900-SWB#show spantree 1

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0004.C1DD.5780

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 32768, address 0003.6B33.42C0

   Root port is FastEthernet 0/26, cost of root path is 10

   Topology change flag not set, detected flag not set

   Topology changes 2, last topology change occured 0d00h00m48s ago

   Times:  hold 1, topology change 8960

           hello 2, max age 20, forward delay 15

   Timers: hello 2, topology change 35, notification 2

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Blocking

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 2(B): Verifying the information of Spanning Tree Protocol on the

                        FastEthernet0/26 interface of 1900-SWB Switch.

1900-SWB#show interfaces fastEthernet 0/26

FastEthernet 0/26 is Enabled

Hardware is Built-in 100Base-TX

Address is 0004.C1DD.579A

MTU 1500 bytes, BW 100000 Kbits

802.1d STP State:  Forwarding     Forward Transitions:  1

Port monitoring: Disabled

Unknown unicast flooding: Enabled

Unregistered multicast flooding: Enabled

Description:

Duplex/Flow Control setting: Auto-negotiate

Auto-negotiation status:  Full duplex

Enhanced Congestion Control: Disabled

Step 2(C): Verifying the information of Spanning Tree Protocol on the

                        FastEthernet0/27 interface of 1900-SWB Switch.

1900-SWB#show interfaces fastEthernet 0/27

FastEthernet 0/27 is Blocking

Hardware is Built-in 100Base-TX

Address is 0003.6B33.42DB

MTU 1500 bytes, BW 100000 Kbits

802.1d STP State:  Forwarding     Forward Transitions:  1

Port monitoring: Disabled

Unknown unicast flooding: Enabled

Unregistered multicast flooding: Enabled

Description:

Duplex/Flow Control setting: Auto-negotiate

Auto-negotiation status:  Full duplex

Enhanced Congestion Control: Disabled

Step 3: Select Root Port By Changing Priority Of Ports On 1900-SWA (Root

                 Switch).

 

1900-SWA(config)#interface fastEthernet 0/27

1900-SWA(config-if)#spantree priority 112

Step 4(A): Verifying the results by Changing Priority Of Ports On 1900-SWA

                        (Root Switch).

Note: After 50 sec’s, the port will be forwarded after taking part into election.

1900-SWA#show spantree

OR

1900-SWA#show spantree 1

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0003.6B33.42C0

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 32768, address 0003.6B33.42C0

   Root port is N/A, cost of root path is 0

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Forwarding

   Port path cost 10, Port priority 112

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 4(B): Verifying the results by changing Priority Of Ports On 1900-SWB

                        (Non-Root Switch).

 

1900-SWB#show spantree

OR

1900-SWB#show spantree 1

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0004.C1DD.5780

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 32768, address 0003.6B33.42C0

   Root port is FastEthernet 0/27, cost of root path is 10

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Blocking

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 32768, address 0003.6B33.42C0

   Designated bridge has priority 32768, address 0003.6B33.42C0

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 5: Change the 1900-SWB (Non-Root Switch) to a Root Switch.

1900-SWB(config)#spantree-template 1 priority 28672

Step 6(A): Verifying the results of new Root Switch on 1900-SWA ( Old Root

                        Switch).

1900-SWA#show spantree

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0003.6B33.42C0

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 28672, address 0004.C1DD.5780

   Root port is FastEthernet 0/26, cost of root path is 10

   Topology change flag not set, detected flag not set

   Topology changes 11, last topology change occured 0d00h05m53s ago

   Times:  hold 1, topology change 8960

           hello 2, max age 20, forward delay 15

   Timers: hello 2, topology change 35, notification 2

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Blocking

   Port path cost 10, Port priority 112

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 6(B): Verifying the results of new Root Switch on 1900-SWB ( New Root

                        Switch).

1900-SWB#show spantree

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 28672, address 0004.C1DD.5780

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 28672, address 0004.C1DD.5780

   Root port is N/A, cost of root path is 0

   Topology change flag not set, detected flag not set

   Topology changes 6, last topology change occured 0d00h09m14s ago

   Times:  hold 1, topology change 8960

           hello 2, max age 20, forward delay 15

   Timers: hello 2, topology change 35, notification 2

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Forwarding

   Port path cost 10, Port priority 128

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Step 7: Select Root Port By Changing Cost Of Ports On 1900-SWA (Non-Root

                 Switch).

                               

1900-SWA(config)#interface fastEthernet 0/27

1900-SWA(config-if)#spantree cost 9

Step 8(A): Verifying the results by changing cost on 1900-SWA (Non-Root

                        Switch).

1900-SWA#show spantree

OR

1900-SWA#show spantree 1

VLAN1 is executing the IEEE compatible Spanning Tree Protocol

   Bridge Identifier has priority 32768, address 0003.6B33.42C0

   Configured hello time 2, max age 20, forward delay 15

   Current root has priority 28672, address 0004.C1DD.5780

   Root port is FastEthernet 0/27, cost of root path is 9

   Topology change flag not set, detected flag not set

   Topology changes 12, last topology change occured 0d00h01m31s ago

   Times:  hold 1, topology change 8960

           hello 2, max age 20, forward delay 15

   Timers: hello 2, topology change 35, notification 2

<Output Omitted>

Port FastEthernet 0/26 of VLAN1 is Blocking

   Port path cost 10, Port priority 128

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 26, path cost 0

   Timers: message age 20, forward delay 15, hold 1

Port FastEthernet 0/27 of VLAN1 is Forwarding

   Port path cost 9, Port priority 112

   Designated root has priority 28672, address 0004.C1DD.5780

   Designated bridge has priority 28672, address 0004.C1DD.5780

   Designated port is 27, path cost 0

   Timers: message age 20, forward delay 15, hold 1