Retrieves the status of an SMS Modem via smstools3.

This plugin checks the status of an SMS modem using the regular_run functionality provided in smstools3.
It does not directly access the modem, but instead reads a status file generated by smstools3.


This plugin works with smstools3 and the regular_run functionality to check the status of a modem (signal strength, GSM Provider etc.). By not accessing the modem directly, we don't have any concurrent access problems. N.B. this script was developed for the MultiTech Network Modems, but should function with any standard GSM modem.


check_sms3status [options] <status_file>

In order to work the following options need to be set in smsd.conf:

regular_run_interval = 60
regular_run_cmd = AT+CREG?;+CSQ;+COPS?
regular_run_statfile = <status_file>

The following performance data is returned

<signal dBm>;<% signal strength>;<Error rate>;<Network ID/Name>


<status_file> the status file e.g. /dev/shm/sms_stat


--warningwarning level for percentage signal strength (default 40)
--criticalcritical level for percentage signal strength (default 20)
--timeouthow long to wait for the file (default 30)
--agethe maximum age of the file in seconds (default 300)


This work is made available to you under the terms of Version 2 of the GNU General Public License. A copy of that license should have been provided with this software, but in any event can be snarfed from

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(The following paragraph is not intended to limit the rights granted to you to modify and distribute this software under the terms of the GNU General Public License and is only of importance to you if you choose to contribute your changes and enhancements to the community by submitting them to NETWAYS GmbH.)

By intentionally submitting any modifications, corrections or derivatives to this work, or any other work intended for use with this Software, to NETWAYS GmbH, you confirm that you are the copyright holder for those contributions and you grant NETWAYS GmbH a nonexclusive, worldwide, irrevocable, royalty-free, perpetual, license to use, copy, create derivative works based on those contributions, and sublicense and distribute those contributions and any derivatives thereof.

Nagios and the Nagios logo are registered trademarks of Ethan Galstad.


16.11.2009 - Perfdata Patch contributed by Gerd v. Egidy