Nagios - Time within nagios is incorrect

Platform :
FreeBSD

Server :
Nagios

Problem :
Nagios's time stamp are incorrect, e.g. the comments section, the log file's time stamp. But the server's date, time & time zone are correct.

Cause :
Nagios configuration needs to specify the time zone offset, as well as the Apache's CGI module. These both settings make sure that nagios's time is in sync with the server's time.

Solution :

Nagios - Error "Error: Could not open command file '/var/spool/nagios/rw/nagios.cmd' for update"

After an upgrade of Nagios, Nagios re-schedule function for next service check is not working. The Nagios web interface complained "Error: Could not open command file '/var/spool/nagios/rw/nagios.cmd' for update". Its problem lies on the webserver was unable to access the file to update the schedule.