Basic VLAN Operation

I am performing a basic operation of VLAN using Packet Tracer.

Topology

It resembles a use case scenario, where 2 PC's from Marketing and Finance are placed in two different buildings.  Each building will have a 3560 multi-layer switch.  A connection is laid between switches.  We need connectivity between MKT-1 and MKT-2.  Also between FIN-1 and FIN-2.

Task Breakdown

1. Setting Devices
2. Creating VLANs in Switch
3. Access Mode Configuration in Switch
4. Trunk Mode Configuration in Switch
5. Validating

1. Setting Devices

• Configure IP Address in PC: Click on PC. Config -> FastEthernet0 -> Static -> 172.1.0.1
• Set hostname in Switch

IP Configuration on PC

Switch#configure t
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)#hostname BLD-1
BLD-1(config)#

Similarly configure IP Addresses and hostnames for all PCs and Switches as mentioned in Topology diagram above.

2. Creating VLANs in Switch

On both BLD-1 and BLD-2 switches create VLANs 2 and 3 for Marketing and Finance respectively.

BLD-1#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
BLD-1(config)#vlan 2
BLD-1(config-vlan)#name MKT
BLD-1(config-vlan)#exit
BLD-1(config)#vlan 3
BLD-1(config-vlan)#name FIN
BLD-1(config-vlan)#exit
BLD-1(config)#exit

Observe that 2 VLANs are created waiting for the ports to be assigned.

BLD-1#show vlan

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/1, Fa0/2, Fa0/3, Fa0/4
                                                Fa0/5, Fa0/6, Fa0/7, Fa0/8
                                                Fa0/9, Fa0/10, Fa0/11, Fa0/12
                                                Fa0/13, Fa0/14, Fa0/15, Fa0/16
                                                Fa0/17, Fa0/18, Fa0/19, Fa0/20
                                                Fa0/21, Fa0/22, Fa0/23, Fa0/24
                                                Gig0/1, Gig0/2
2    MKT                              active    
3    FIN                              active    
1002 fddi-default                     active    
1003 token-ring-default               active    
1004 fddinet-default                  active    
1005 trnet-default                    active   

3. Access Mode Configuration in Switch

• Fa0/1 of BLD-1 to VLAN 2(MKT)
• Fa0/2 of BLD-1 to VLAN 3(FIN)
• Fa0/1 of BLD-2 to VLAN 2(MKT)
• Fa0/2 of BLD-2 to VLAN 3(FIN)

Now we have to assign ports of switches to VLANs 2 or 3 according to the PCs connected.  Here in our case:

BLD-1(config)#int fa0/1
BLD-1(config-if)#switchport access vlan 2
BLD-1(config-if)#switchport mode access
BLD-1(config-if)#exit
BLD-1(config)#int fa0/2
BLD-1(config-if)#switchport access vlan 3
BLD-1(config-if)#exit
BLD-1(config)#exit


Observe the Port assignments to VLAN

BLD-1# show vlan

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/3, Fa0/4, Fa0/5, Fa0/6
                                                Fa0/7, Fa0/8, Fa0/9, Fa0/10
                                                Fa0/11, Fa0/12, Fa0/13, Fa0/14
                                                Fa0/15, Fa0/16, Fa0/17, Fa0/18
                                                Fa0/19, Fa0/20, Fa0/21, Fa0/22
                                                Fa0/23, Fa0/24, Gig0/1, Gig0/2
2    MKT                              active    Fa0/1
3    FIN                              active    Fa0/2
1002 fddi-default                     active    
1003 token-ring-default               active    
1004 fddinet-default                  active    
1005 trnet-default                    active    

4. Trunk Mode Configuration in Switch

Interconnection of two Switches is through Gig0/1.  They have to pass traffic of VLANs 1 and 2 in it.  So, we make it Trunk mode with encapsulation IEEE Dot11q.

The configuration to be performed on both BLD-1 and BLD-2

BLD-1(config)#int gig0/1
BLD-1(config-if)#switchport trunk encapsulation dot1q
BLD-1(config-if)#switchport mode trunk
BLD-1(config-if)#exit
BLD-1(config)#exit

As Default VLAN 1 is already present in switch and we added VLAN 2 and 3, the resultant trunk port will pass all 3 VLANs traffic.

BLD-2#show int trunk
Port        Mode         Encapsulation  Status        Native vlan
Gig0/1      on           802.1q         trunking      1

Port        Vlans allowed on trunk
Gig0/1      1-1005

Port        Vlans allowed and active in management domain
Gig0/1      1,2,3

Port        Vlans in spanning tree forwarding state and not pruned
Gig0/1      1,2,3

5. Validating

To make sure our configuration works (without negative test cases involved), Following ping test should pass

• MKT-1 (172.1.0.1) to MKT-2 (172.1.0.2)
• FIN-1 (172.2.0.1) to FIN-2 (172.2.0.2)

Click FIN-1. Desktop -> Command Prompt