How to Configure VLANs on Cisco Switches (Step-by-Step Guide)

Introduction

In today’s enterprise networks, Virtual LANs (VLANs) are essential for improving performance, security, and traffic management. By dividing a single switch into multiple logical networks, VLANs help reduce broadcast domains and isolate traffic for different departments such as Sales, HR, or IT.

We’ll walk step-by-step through VLAN configuration on Cisco switches using CLI commands. Whether you are setting up a lab for CCNA or configuring VLANs in a production environment, this guide will give you everything you need.

Prerequisites / Requirements

Before you begin, make sure you have:

• Cisco switch (physical or in GNS3/EVE-NG/Packet Tracer).
• Console/SSH access to the switch.
• Basic understanding of IP addressing and switching concepts.

Step-by-Step Configuration

Step 1: Access the Switch

Use console or SSH to connect to your switch.

   ssh admin@192.168.1.1

Enter privileged EXEC mode:

    Switch> enable
    Switch#

Step 2: Create VLANs

Create VLANs and assign names:

    Switch(config)# vlan 10
    Switch(config-vlan)# name SALES
    Switch(config-vlan)# exit
    
    Switch(config)# vlan 20
    Switch(config-vlan)# name HR
    Switch(config-vlan)# exit

Step 3: Assign VLAN to Interfaces

Assign access ports to VLANs:

Switch(config)# interface fastEthernet 0/1
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan 10
Switch(config-if)# exit

Switch(config)# interface fastEthernet 0/2
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan 20
Switch(config-if)# exit 

Step 4: Save Configuration

Make sure to save the configuration so it persists after reboot:

Switch# write memory

or

Switch# copy running-config startup-config    

Verification

Check VLANs configured:

`Switch# show vlan brief`

Expected output:

    VLAN Name                             Status    Ports
    1    default                          active    Fa0/3, Fa0/4
    10   SALES                            active    Fa0/1
    20   HR                               active    Fa0/2

Troubleshooting Tips

• If VLANs don’t appear, check with show running-config.
• Ensure interface is not in trunk mode when assigning access VLAN.
• Always verify cables and connectivity between devices.

Summary

• VLANs logically divide a switch into multiple broadcast domains.
• Configuration involves creating VLANs and assigning them to ports.
• Verification is done with show vlan brief.

That’s it! You’ve successfully created and assigned VLANs on a Cisco switch. 🎉

👉 If you’re preparing for CCNA or managing enterprise networks, VLANs are one of the most fundamental skills you’ll use every day.

💬 Got questions or stuck in configuration? Drop a comment below — or contact Netvorx Pro Pvt Ltd for professional network setup and 24/7 support.