Configure VLAN, STP, DTP tutorial

How to Configure VLAN, STP, DTP ?

In this tutorial we will study step by step process and how can you,

• Configure Access or trunk links
• Create VLAN
• Assign VLAN membership
• Configure Intra VLAN routing
• Configure VTP server  
• Make VTP Clients
• Show STP Static
• Configure DTP Port

To complete these labs work either create a topology as shown in figure or downloads this file and loads it in packet tracer version 7.0.

Task is lets assume that you are the administrator of Cisco company have two department sales and management. You have given three PC for sales and three PC in management. You created two VLAN. VLAN 10 for sales and VLAN20 for management. For backup purpose you have interconnected switch with one extra connection. You have one router for inters VLAN communications.

Let’s start configuration first assign IP address to all PC’s

Device         ip address

PC0                10.0.0.2

PC1                20.0.0.2

PC2                10.0.0.3

PC3                20.0.0.3

PC4                10.0.0.4

PC5                10.0.0.4

VLAN Trunking Protocol

Configure VTP Server

We will first create a VTP Server so it can automatically propagate VLAN information to other switch. Double click on Switch1 and select CLI. Set hostname to S1 and create VTP domain name example and set password to cisco (Remember password is case sensitive).

Switch 1 

Switch>enable

Switch#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Switch(config)#hostname S1

S1(config)#vtp mode server

Device mode already VTP SERVER.

S1(config)#vtp domain example

Changing VTP domain name from NULL to example

S1(config)#vtp password cisco

Setting device VLAN database password to cisco

Configure VTP Clients

Once you have created a VTP domain. Configure remaining Switch to Client mode.

Switch 2

Switch>enable

Switch#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Switch(config)#hostname S2

S2(config)#vtp mode client

Setting device to VTP CLIENT mode.

S2(config)#vtp domain example

Changing VTP domain name from NULL to example

S2(config)#vtp password cisco

Setting device VLAN database password to cisco

S2(config)#exit

Switch 3

Switch>enable

Switch#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Switch(config)#hostname S3

S3(config)#vtp mode client

Setting device to VTP CLIENT mode.

S3(config)#vtp domain example

Changing VTP domain name from NULL to example

S3(config)#vtp password cisco

Setting device VLAN database password to cisco

S3(config)#exit

Dynamic Trunking Protocol

Configure DTP port

All Switch ports remain by default in access mode. Access port can not transfer the trunk frame. Change mode to trunk on all the port those are used to interconnect the switches.

Switch 1

S1(config)#interface fastEthernet 0/24

S1(config-if)#switchport mode trunk

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/24,

changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/24,

changed state to up

S1(config-if)#exit

S1(config)#interface gigabitEthernet 0/1

S1(config-if)#switchport mode trunk

S1(config-if)#exit

S1(config)#interface gigabitEthernet 0/2

S1(config-if)#switchport mode trunk

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2,

changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2,

changed state to up

S1(config-if)#exit

S1(config)#exit

Switch 2

S2(config)#interface gigabitEthernet 0/1

S2(config-if)#switchport mode trunk

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/1,

changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/1,

changed state to up

S2(config-if)#exit

S2(config)#interface gigabitEthernet 0/1

S2(config-if)#switchport mode trunk

S2(config-if)#exit

S2(config)#interface fastEthernet 0/23

S2(config-if)#switchport mode trunk

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23,

changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/23,

changed state to up

S2(config-if)#exit

S2(config)#interface fastEthernet 0/24

S2(config-if)#switchport mode trunk

S2(config-if)#exit

Switch 3

S3(config)#interface fastEthernet 0/24

S3(config-if)#switchport mode trunk

S3(config-if)#exit

S3(config)#interface gigabitEthernet 1/1

S3(config-if)#switchport mode trunk

S3(config-if)#exit

Virtual LAN (VLAN)

Create VLAN

After VTP server configuration it’s time to organize VLAN. We need only to create VLAN on VTP server and reset will be done by VTP Server automatically.

Switch 1

S1(config)#vlan 10

S1(config-vlan)#exit

S1(config)#vlan 20

S1(config-vlan)#exit

S1(config)#exit

As we have already configured VTP server in our network so we don’t need to create VLAN on S2 or S3. We need only to associate VLAN with port.

Assign VLAN membership

Switch 1

S1(config)#interface fastEthernet 0/1

S1(config-if)#switchport access vlan 10

S1(config-if)#interface fastEthernet 0/2

S1(config-if)#switchport access vlan 20

Switch 2

S2(config)#interface fastEthernet 0/1

S2(config-if)#switchport access vlan 10

S2(config-if)#interface fastEthernet 0/2

S2(config-if)#switchport access vlan 20

Switch 3

S3(config)#interface fastEthernet 0/1

S3(config-if)#switchport access vlan 10

S3(config-if)#interface fastEthernet 0/2

S3(config-if)#switchport access vlan 20

Now we have two working vlan. To test connectivity do ping form 10.0.0.2 to 10.0.0.3 and 10.0.0.4. if you get successfully replay then you have successfully created VLAN and VTP server.

Spanning-Tree Protocol

In this configuration STP will block these ports F0/24 of S1 , F0/23 and F0/24 of S2 and F0/24 of S3 to avoid loop at layer to two. Verify those ports blocked due to STP functions.

Verify STP ports

Switch 2

You can test STP protocols status on S1 and S3 also with

show spanning-tree active command

Router on Stick

At this point of configuration you have two successfully running VLAN but they will not connect each other. To make intra VLAN communications we need to configure router . To do this double click on router and select CLI.

Configure intra VLAN

Router

Router>enable

Router#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#interface fastEthernet 0/0

Router(config-if)#no ip address

Router(config-if)#no shutdown

Router(config-if)#exit

Router(config)#interface fastEthernet 0/0.10

Router(config-subif)#encapsulation dot1Q 10

Router(config-subif)#ip address 10.0.0.1 255.0.0.0

Router(config-subif)#exit

Router(config)#interface fastEthernet 0/0.20

Router(config-subif)#encapsulation dot1Q 20

Router(config-subif)#ip address 20.0.0.1 255.0.0.0

Router(config-subif)#exit

To test connectivity between different vlan do ping form any PC to all reaming PC. it should be ping successfully. If you have error download this configured topology and cross check that where you have committed mistake.

Therefore, we have completed our lab work successfully by using VLAN, STP, and DTP configurations.