Security Fundamentals Fix ~4 min

Port-security err-disabled Fa0/1 — Recover it

Fa0/1 is a port-secured access port (max 1 MAC, violation shutdown). A user quietly plugged a hub with a second laptop into the jack; the violation fired and Fa0/1 went err-disabled. The rogue device has been removed. Bring Fa0/1 back into service.

SW1

Objective

○Fa0/1 recovered (not err-disabled and not shutdown)

Hints

Hint — how to recover

A `no shutdown` alone won't clear err-disable. You have to shutdown first, then no shutdown.

enable
configure terminal
 interface fa0/1
  shutdown
  no shutdown
  end
show port-security interface fa0/1