Define a service check for all hosts of a group except one

define service{
      service_description     CPU Stats
      servicegroups   sysres
      use             generic
      hostgroup_name  linux
      host_name       !server1
      check_command   check_iostat

Auto create a host and services configs by scanning ports with nmap

nmap -sS -O -oX nmap.xml -v -r nmap.xml -o new.cfg

Define OS of a host

define hostextinfo{
    host_name       server1
    icon_image      debian.png
    icon_image_alt  Debian
    vrml_image      debian.png
    statusmap_image debian.gd2

Check config for errors

nagios -v /etc/nagios/nagios.cfg

Convert timestamps of nagios.log

perl -pe 's/(\d+)/localtime(jumi)/e' nagios.log

Nagios statistical graphs