Nov 19 15:46:59 jarfx start_apache2[18984]: AH00526: Syntax error on line 15 of /etc/apache2/conf.d/nagios.conf:
Nov 19 15:46:59 jarfx start_apache2[18984]: Invalid command 'Order', perhaps misspelled or defined by a module not included in the server configuration
This is strange... we place nagios.conf in "/etc/apache2/conf-enabled" directory, NOT in "/etc/apache2/conf.d/"... Can you upload the nagios.conf on the forum?
Also, run the following commands and show the output: