How to Configure SPAN (Port Mirroring) on a Cisco Switch | GNS3 Step-by-Step Lab
In this video, I demonstrate how to configure SPAN (Switched Port Analyzer) on a Cisco switch using GNS3. SPAN, also known as port mirroring, allows a switch to copy network traffic from one port or VLAN and send it to another port for monitoring and analysis.
This technique is widely used in network troubleshooting, security monitoring, and packet analysis with tools like Wireshark.
In this lab demonstration, you will see:
• How SPAN works conceptually
• How two PCs communicate through a switch
• How the switch mirrors the traffic to a third monitoring PC
• Step-by-step Cisco CLI configuration of SPAN
• How to verify that mirrored traffic is being captured
This is a useful concept for networking students, CCNA learners, cybersecurity students, and network administrators who want to understand how traffic monitoring works inside a switch.
The demonstration is done completely in GNS3, making it easy for you to replicate the lab on your own system.
Network Device Image used in the lab:
https://drive.google.com/file/d/1N1Zx...
If you are learning computer networking, packet analysis, or switch configuration, this practical example will help you visualize how SPAN works in a real environment.
Topics covered:
SPAN configuration
Port mirroring on Cisco switch
Network traffic monitoring
GNS3 networking lab
Packet capture concepts
Cisco switch CLI configuration