This is a text-only version of the following page on https://raymii.org:
---
Title       : 	Nagios plugin to check certificates on local file system
Author      : 	Remy van Elst
Date        : 	24-09-2012
URL         : 	https://raymii.org/s/software/Nagios_check_local_certificate_files.html
Format      : 	Markdown/HTML
---



This tutorial will show you how you can use the nagios plugin "check _ssl_ cert"
to monitor locally stored SSL certificates.

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### Installing the nagios-plugin

The plugin needs the expect program to be installed on the hosts which will
check their certificates.

Install it with the following command:

    
    
    sudo apt-get install expect
    

Now install the plugin:

    
    
    sudo wget -O /etc/nagios-plugins/check_ssl_cert --no-check-certificate https://trac.id.ethz.ch/projects/nagios_plugins/export/1315/check_ssl_cert/check_ssl_cert
    

Also, make it executable:

    
    
    sudo chmod +x /etc/nagios-plugins/check_ssl_cert
    

### Setting up the host

On the nagios client where the certificates are, you have to edit the NRPE
config to do the checks locally

    
    
    vim /etc/nagios/nrpe_local.cfg
    

Add:

    
    
    command[check_local_ssl]=/etc/nagios-plugins/check_ssl_cert -H localhost -f /home/so_ad/7days.pem -c 30
    command[check_local_ssl]=/etc/nagios-plugins/check_ssl_cert -H localhost -f /home/so_ad/7days.pem -c 5    
    

### Setting up the nagios server

I have the hostgroup _nodes_ defined, and in my nagios config file I add the
following service:

    
    
    vim /etc/nagios3/conf.d/services-hostgroups.cfg
    

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---

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