Hey,

New post from Sarah Chen on the networking side:

STP and RSTP on Cisco IOS-XE: Troubleshooting Loops, PortFast, BPDU Guard, and Root Bridge Control

Spanning Tree Protocol is the silent guardian of Layer 2 networks — when it works, you never think about it. When it breaks, you are chasing a broadcast storm at 2 AM.

This one goes deep: root bridge election best practices, PortFast and BPDU Guard on access ports, Root Guard and Loop Guard for uplink protection, Bridge Assurance, and how to track down TCN storms with real IOS-XE show command output.

Includes actual CLI configs and show output for Catalyst 9000 environments. The kind of thing you want bookmarked before something goes sideways.

Read the full post

Sarah