pm-4-err_disable – the switchport is down
If an error occurs on your network, the professional series of Cisco switches would probably shutdown the the network port where the error is detected.
Even if the error on the network is corrected, the network port is still down. You have to enable it manually.
The switch is able to automatically enable the port. If the root error on the network remains, the port is immediately shutdown again.
To check the configuration, use this command:
show errdisable recovery
If something is disabled, it means you manually have to activate the port if this specific error has occurred.
It can all be done automatically with this commands:
errdisable recovery cause udld
errdisable recovery cause bpduguard
errdisable recovery cause security-violation
errdisable recovery cause channel-misconfig
errdisable recovery cause pagp-flap
errdisable recovery cause dtp-flap
errdisable recovery cause link-flap
errdisable recovery cause gbic-invalid
errdisable recovery cause psecure-violation
errdisable recovery cause dhcp-rate-limit
errdisable recovery cause unicast-flood
errdisable recovery cause vmps
errdisable recovery cause storm-control
errdisable recovery cause loopback
errdisable recovery cause sfp-config-mismat
