I very new to nagios and linux but how do I change a notification that state a server is down it due it configured to an old ip how do I changed it please simple steps
Go to
/etc/nagiosX/conf.d
folder, where X is the number of your Nagios version (should be 2 or 3) and there should be configuration files (all with the .cfg extension).
Anyway, you should know where your configuration files are stored. In them you must find host definition for your server. In that definition go to
address
variable and replace the old IP address with the new one.
Reload the Nagios.
That shoud be it.