Regarding Logging of state in alerts at every rechecks

[scottwilkerson]

i read on internet is that if the service and host is both down in nagios
by logically nagios won't check the service as it knows when the host down is down

Actually this is wrong. If the host is down the service will not send a notification, but by default it will still perform the check.

[npolovenko]

@shubham, In addition to what Scott said, I'd like to point out that if you're still seeing the behavior where services would stop getting checked when the host is down, I recommend checking the /usr/local/nagios/etc/nagios.cfg file and making sure that this option is set to 0.

host_down_disable_service_checks=1