Editing Main Page/Nagios add Indirect Host and Service Checks (section)

== on directly accessible  ( primary ) server : ==

1. Access mail-server ( server already mapped as directly accesible )

2. Install check_nrpe plugin if not present 

# yum install nagios-plugins-nrpe

3. now add entry in nrpe.cfg for each service you want to check on the secondary/passive server as shown below :

COMMANDS FOR MAIN SERVER

command[check_users]=/usr/local/nagios/libexec/check_users -w 5 -c 10

command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20

command[check_hda1]=/usr/local/nagios/libexec/check_disk -w 7% -c 5% -p /dev/sda3

command[check_zombie_procs]=/usr/local/nagios/libexec/check_procs -w 5 -c 10 -s Z

command[check_cpu]=/usr/local/nagios/libexec/check_cpu.sh -w 60 -c 70

command[check_mem]=/usr/local/nagios/libexec/check_mem_avail -w 130 -c 150

command[check_clam]=/usr/local/nagios/libexec/check_clamd -H localhost

command[check_queue]=/usr/local/nagios/libexec/check_postfix_queue -w 300 -c 500

command[check_zimbra_clam_ud]=sudo -u zimbra /usr/local/nagios/libexec/check_clamav -w 2 -c 5

command[check_zimbra_lmtp]=/usr/local/nagios/libexec/check_smtp -H localhost -p 7025 -e '220 zimbraserver.2coms.com Zimbra LMTP server ready'

'''# following commands are for backup server 192.168.1.5'''

command[check_users2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_users

command[check_load2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_load

command[check_hda12]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_hda1

command[check_hda22]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_hda2

command[check_hda32]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_hda3

command[check_zombie_procs2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_zombie_procs

command[check_cpu2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_cpu

command[check_mem2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_mem

command[check_clam2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_clam

command[check_queue2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_queue

command[check_zimbra_lmtp2]=/usr/local/nagios/libexec/check_nrpe -H 192.168.1.5 -c check_zimbra_lmtp