The below output is given when checking the status of the NRPE service on the client.
nrpe.service - Daemon to remotely execute Nagios plugins
Loaded: loaded (/<filepath>/nrpe.service; enabled)
Active: failed (Result: exit-code) since Fri 2016-10-28 09:09:15 MDT; 43s ago
Main PID: 3750 (code=exited, status=2)
Oct 28 09:09:15 <server-name> nrpe[3750]: Starting up daemon
Oct 28 09:09:15 <server-name> nrpe[3750]: Cannot write to pidfile '/<filepath>/nrpe.pid' - check your privileges.
This is syslog output when starting NRPE client:
2016-10-28T09:43:33.246746-06:00 <server-name> nrpe[4643]: Added command[check_users]=/<filepath>/nagios/plugins/check_users -w 5 -c 10
2016-10-28T09:43:33.247269-06:00 <server-name> nrpe[4643]: Added command[check_load]=/<filepath>/nagios/plugins/check_load -w 15,10,5 -c 30,25,20
2016-10-28T09:43:33.247607-06:00 <server-name> nrpe[4643]: Added command[check_disk]=/<filepath>/nagios/plugins/check_disk -w 20% -c 10% -p /
2016-10-28T09:43:33.247860-06:00 <server-name> nrpe[4643]: Added command[check_zombie_procs]=/<filepath>/nagios/plugins/check_procs -w 5 -c 10 -s Z
2016-10-28T09:43:33.248108-06:00 <server-name> nrpe[4643]: Added command[check_total_procs]=/<filepath>/nagios/plugins/check_procs -w 250 -c 300
2016-10-28T09:43:33.249014-06:00 <server-name> nrpe[4643]: INFO: SSL/TLS initialized. All network traffic will be encrypted.
2016-10-28T09:43:33.249627-06:00 <server-name> nrpe[4644]: Starting up daemon
2016-10-28T09:43:33.250140-06:00 <server-name> nrpe[4644]: Cannot write to pidfile '/<filepath>/nrpe.pid' - check your privileges.
you can use chmod nagios:nagios /var/run/nrpe/nrpe.pid, if .pid file exists at the location.or use grep to find the location and the apply chmod.