This is a script that presents information about unused (notconnect according to "show interface status" on Cisco switches) ports on (Cisco and probably other) switches.

The script outputs how many unused ports there are right now, and the names of the ports with the amount of days they have been "down".

If the switch is a Cisco and the not connected port is configured with a VLAN number, the VLAN number is also printed.

The output is almost the same as the output from "sh interfaces status | include not" but with the number of days and VLAN.

The number of unused ports is also sent as performance data so that it can be graphed.

The script saves the names of all the not connected ports with a timestamp so that the information will be available even if the switch is rebooted.

The information about the ports is retrieved with SNMP.

Cisco switches reset the switchport status when rebooted. Due to this the script saves the status in text files. There will be one file created per switch. Make sure that the user running the script is able to write and read these files. There is a variable at the top of the script that points to a directory where these files are saved.


Edit the script and make sure that the variable "tempdir" points to a directory that is writable by the user running the script (Usually nagios, icinga or monitor).

Also make sure that the variable "snmpwalk" points to snmpbulkwalk.

Add this script as a service check for a switch in Op5 Monitor/Nagios/Icinga or whichever compatible monitoring system is your choice.

Apply the SNMP authentication information as variables to the service.

Define the command for example like this for SNMPv3: $HOSTADDRESS$ username SHA $ARG1$ AES $ARG2$

and for SNMPv2c: $HOSTADDRESS$ $ARG1$

Where ARG1 is the community string.

In case you have a setup with several monitoring peers, it might be usable to rsync the "tempdir" from crontab every now and then so that the latest information about the switches is available to all the peers.


I have tested this script with Cisco Catalyst 2960G, 2960-S, 2960-X and 3750G.

It should however work with other models and brands.

Let me know if you have a switch that supports SNMP and works or doesn't with this plugin.

Version history

  • 1.2 2016-07-15 Added information about the VLAN on the not connected interface.
  • 1.1 2016-07-15 Fixed a critical bug.
  • 1.0 2016-06-15 Initial version.

Licensed under the Apache License Version 2.0

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