[root@monitors libexec]# ./check_nrpe -h  

NRPE Plugin for Nagios
Copyright (c) 1999-2008 Ethan Galstad ([email protected])
Version: 3.0.1
Last Modified: 09-08-2016
License: GPL v2 with exemptions (-l for more info)
SSL/TLS Available: OpenSSL 0.9.6 or higher required

Usage: check_nrpe -H <host> [-2] [-4] [-6] [-n] [-u] [-V] [-l] [-d <dhopt>]
       [-P <size>] [-S <ssl version>]  [-L <cipherlist>] [-C <clientcert>]
       [-K <key>] [-A <ca-certificate>] [-s <logopts>] [-b <bindaddr>]
       [-f <cfg-file>] [-p <port>] [-t <interval>:<state>]
       [-c <command>] [-a <arglist...>]

Options:
 <host>       = The address of the host running the NRPE daemon
 -2           = Only use Version 2 packets, not Version 3
 -4           = bind to ipv4 only
 -6           = bind to ipv6 only
 -n           = Do no use SSL
 -u           = (DEPRECATED) Make timeouts return UNKNOWN instead of CRITICAL
 -V           = Show version
 -l           = Show license
 <dhopt>      = Anonymous Diffie Hellman use:
                0 = Don't use Anonymous Diffie Hellman
                    (This will be the default in a future release.)
                1 = Allow Anonymous Diffie Hellman (default)
                2 = Force Anonymous Diffie Hellman
 <size>       = Specify non-default payload size for NSClient++
 <ssl ver>    = The SSL/TLS version to use. Can be any one of: SSLv2 (only),
                SSLv2+ (or above), SSLv3 (only), SSLv3+ (or above),
                TLSv1 (only), TLSv1+ (or above DEFAULT), TLSv1.1 (only),
                TLSv1.1+ (or above), TLSv1.2 (only), TLSv1.2+ (or above)
 <cipherlist> = The list of SSL ciphers to use (currently defaults
                to "ALL:!MD5:@STRENGTH". WILL change in a future release.)
 <clientcert> = The client certificate to use for PKI
 <key>        = The private key to use with the client certificate
 <ca-cert>    = The CA certificate to use for PKI
 <logopts>    = SSL Logging Options
 <bindaddr>   = bind to local address
 <cfg-file>   = configuration file to use
 [port]       = The port on which the daemon is running (default=5666)
 [command]    = The name of the command that the remote daemon should run
 [arglist]    = Optional arguments that should be passed to the command,
                separated by a space.  If provided, this must be the last
                option supplied on the command line.

 NEW TIMEOUT SYNTAX
 -t <interval>:<state>
    <interval> = Number of seconds before connection times out (default=10)
    <state> = Check state to exit with in the event of a timeout (default=CRITICAL)
    Timeout state must be a valid state name (case-insensitive) or integer:
    (OK, WARNING, CRITICAL, UNKNOWN) or integer (0-3)

Note:
This plugin requires that you have the NRPE daemon running on the remote host.
You must also have configured the daemon to associate a specific plugin command
with the [command] option you are specifying here.  Upon receipt of the
[command] argument, the NRPE daemon will run the appropriate plugin command and
send the plugin output and return code back to *this* plugin.  This allows you
to execute plugins on remote hosts and 'fake' the results to make Nagios think
the plugin is being run locally.