In a core/edge network topology, Root Guard is a Spanning Tree Protocol (STP) feature that prevents designated ports from becoming root ports. This ensures that the core switch remains the root bridge, maintaining a stable and predictable network topology.

Configuration Steps:

Identify Core Ports Facing the Edge:

Determine which ports on the core switch connect to edge switches.

Enable Root Guard on These Ports:

Access the core switch's configuration mode.

For each identified port, apply the Root Guard configuration:

interface ethernet 1/1/1

spanning-tree root-guard

Replace 1/1/1 with the actual port identifier.

Example Configuration:

arduinoICX(config)# interface ethernet 1/1/1

ICX(config-if-e1000-1/1/1)# spanning-tree root-guard

This configuration ensures that port 1/1/1 on the core switch will not accept superior BPDUs, preventing edge switches from becoming the root bridge.