You can use Nagios to monitor all sorts of hardware and software. The opportunity to write your own plug-ins makes it possible to monitor everything that your Nagios server can communicate with. As you can use any computing language that manages command-line arguments and exit status.
Here you find a nagios pluging developed with python.
The pluging named check_openvpn, it connects to the management OpenVPN server checks for actives connection and return the amount connected OpenVPN clients. it’s forked from openvpn-status scripts.
First of all download the check_openvpn script into your pluging directory on debian it’s /usr/lib/nagios/plugins/.
To use the new plug-in, you have to register it first, create the file command called openvpn.cfg with contents as below:
$ sudo cat > /etc/nagios-plugins/config/openvpn.cfg
define command {
command_name check_openvpn
command_line /usr/lib/nagios/plugins/check_openvpn -t $ARG1$ -p $ARG2$ -n $ARG3$
}
Let’s create some hostgroups – say openvpn-server
$ sudo cat >> /etc/nagios3/conf.d/hostgroups_nagios2.cfg
define hostgroup {
hostgroup_name openvpn-server
alias openvpn servers
members myhost
}
replace vpn.example.com by your openvpn server address, and myhost by the openvpn server name.
Now let’s define those hosts:
$ sudo cat >> /etc/nagios3/conf.d/hosts.cfg
define host {
use generic-host;
host_name myhost;
address vpn.example.com;
}
Now we can define services that run in the new hostgroups
$ sudo cat >> /etc/nagios3/conf.d/services_nagios2.cfg
define service {
hostgroup_name opevpn
service_description OPENVPN
check_command check_openvpn!host!port!passwd
use generic-service
notification_interval 0
}
replace “host” by the address of your openvpn server, “port” by the openvpn management server port and “passwd” by the openvpn nanagement server password.
Don’t forget to check your configuration
$ sudo nagios3 -v /etc/nagios3/nagios.cfg
Then restart the daemon
$ sudo /etc/init.d/nagios3 restart
If all that went well, you should be able to go back to the Hostgroup Overview page on your Nagios install and see the new hostgroups and hosts.
