VLAN is a technology used to partition a single layer 2 network into multiple broadcast domains. This is done to restrict communication between devices that share the same broadcast medium. However, these devices can communicate with one another through a layer 3 device, such as a router. This is similar to connecting devices to different switches and then connecting them all to a router to separate broadcast traffic.

As more and more VLANs are created, it becomes tedious to replicate the configuration across all switches, which was why VTP was created.

We'll first learn about creating VLAN and assigning ports to it. VLAN 1 is created by default on all switches, and all ports reside in it. This VLAN is called the management VLAN.

To create a VLAN, use the following command:

Sw1(config)#vlan 2

The VLAN ID can be between 1 and 1001. The IDs 1002, 1003, 1004, and 1005 are reserved. Once this command has been entered, you are taken to the VLAN subconfiguration mode...