VTP

VTP (VLAN Trunking Protocol)

I am Network Admin at some organization and I have so many switches in my Network. All switches are in same network and connected to each other either directly or indirectly. Now I need to control all switches from my room. Scenario is like---

 

Befits-
  
    If you are using VTP then you don't need to go on each switch you can control from Server Switche. It'll save your time and it is provide security also.

Modes-

  VTP have 3 mode-

1.Server- There should be at-least 1 switch should be in Server mode. In server mode you can create, delete and modify vlan's.

2.Client- In client mode you can't create, delete and modify vlan's. Only you can assign ports to vlan's.

3.Transparent- If you are making some changes on Server Switch then it'll reflect on only Client Switches.It'll not affect Transparent Switch. Transparent switches can forward VTP Traffic without making changes.

Configuration- 

1. Make trunk port to all ports which are connected to another switches.

(Note-- Apply S#show interface switchport 
  Yo can see that--
Administrative Mode: dynamic auto
Operational Mode :Static Access 

So Admin Mode is in Dynamic Auto mode it means if it detect a trunk port on another end it'll convert in Trunk port automatically.So for easiness do this configuration on switch 2 and 3 because these 2 switches are connected to all switches.)

S2#Conf t
S2(config)#interface range fastEthernet 0/1 - 3
S2(config-if-range)#switchport mode trunk


S3(config)#interface range fastEthernet 0/1 - 3
S2(config-if range)#switchport mode trunk

2.Now time to enable VTP on switches for doing this we need to give 3 information to all switches.
   (i) VTP Domain Name
   (ii) VTP Mode
   (iii) VTP Password 

(Note- No need to give Domain name to each switch every time, because when you are configuring VTP domain name on one switch all switches which are directly connected to this switch and have trunk port will have this information.)

(Note- By-default all Cisco switches are in Server mode so no need to configure Mode Server again. So if you want to make a switch client or transparent configure it.)

So on S2 and S3--

S(config)#vtp domain cisco
S(Config)#vtp password ccnp
S(config)#vtp mode client/transparent

on S1--
S(config)# vtp password ccnp

on S4, S5, S6, S7--
S(config)#vtp mode client/transparent
S(config)#vtp password ccnp

(Note---Domain Name and Password must be same in whole network.)

Testing-

Now create VLAN on your server switch and see changes in Client Switches.

To see vlan's-

S# show vlan

 Now apply 

S# show vtp status

By this command you can see- 

VTP Operating Mode---Server or Client which you have set.

VTP Domain Name - ccnp

Configuration Revision - How many changes you have made in vlan's.

And you can see one more thing Maximum Vlans supported locally-255

(Note- Configuration Revision of Transparent switch always zero (0). And if you want to make Configuration Revision no zero to all switch there there are two option first change your domain name another one delete vlan database.

First one you can do easily and for second one-
S# show flash:

now you'll see a database of vlans name as---vlan.dat. You need to delete this database.So-
S#delete vlan.dat and after 2 confirmation it'll delete, and now you can see you status of vtp again.)