The -H [IP or hostname of the openvpn server] and -p options [port of the
openvpn server] are always obligatory. If plugin can be connected with the
management interface it will show the common name (as it is specified in the
client certificate) of the connected clients. Otherwise, it will finish with
critical state. The -i option shows the remote IP address of the client instead
of their common name and the -n option shows the number of connected clients.
It is possible to be verified that a client in particular is connected using
one of these two options -C [common name] or -r [remote IP address]. If these
options are used, also the exit state is due to specify that will give back
plugin if it does not find the client through the -w [warning] -c [critical]
options.

Author:
-------
Jaime Gascon Romero