CHECK_NRPE: Error – Could not complete SSL handshake nagios

The nrpe uses the port no. 5666 to communicate . The same port no. must be opened in nagios server as well as in nagios client.
Usually we see the error “CHECK_NRPE: Error – Could not complete SSL handshake” .It is because nrpe works with ssl and this error tells that nrpe is not able to communicate because there is some SSL issue.
For resolving this issue. Install the ssl in both side nagios server and nagios client. Use the below given command to install openssl package

In CentOS or Red Hat

yum install openssl

In Debian or Ubuntu

sudo apt-get install openssl

Restart the nrpe in both system (nagios server and nagios client)

/etc/init.d/nrpe restart

now check with check_nrpe .

Get the location where check_nrpe is there.

find / -name check_nrpe
You will find where the check_nrpe is located

Use the absolute path of check_nrpe and hit the below command.
In my system the path was /usr/lib/nagios/plugins/check_nrpe, hence I am using same.

/usr/lib/nagios/plugins/check_nrpe -H remote_server_ip

It will show the nrpe version. like this in below given command.
Remote server IP is 192.168.122.94

[root@localhost ~]# /usr/lib/nagios/plugins/check_nrpe -H 192.168.122.94
NRPE v2.13
[root@localhost ~]#