Help configuring Nagios v3 on RedHat


Hi gang…I’m new to Nagios and Linux. I’ve installed linux, Nagios and Apache. I can open the browser and connect to Http://localhost/nagios/ and get the main screen of Nagios. After that none of the links work. So, I know I need to configure Nagios at this point. Now when i test my Nagios configs with:

/usr/local/nagios/bin/nagios -v /etc/nagios/nagios.cfg

I get the following:

Error: Could not find any contact matching ‘nagios’ (config file ‘/etc/nagios/objects/contacts.cfg’, starting on line 51)
Error: Could not expand member contacts specified in contactgroup (config file ‘/etc/nagios/objects/contacts.cfg’, starting on line 51)

I’m really having a hard time with verifying nagios configs and was hoping someone would tell me what config files I need to check. I’ve looked at contacts.cfg but can’t seem to figure out why it’s complaining.

contents of my contacts.cfg file:
define contactgroup{
contactgroup_name nagios
alias Nagios Administrators
members nagios

I have a group called nagios and a user called nagios.


You have to define a contact named nagios in /etc/nagios/objects/contacts.cfg
But I would advise you to specify real contacts that you will use. Read the documentation and defining objects part for that: … bject.html


Thank you Albin…

I’ve gotten past that stage, now I’m banging my head against this issue when i try running

/usr/local/nagios/bin/nagios -v /etc/nagios/nagios.cfg

I get this:

Warning: Duplicate definition found for host ‘dds134’ (config file ‘/etc/nagios/mysite/localhost.cfg’, starting on line 25)
Error: Could not add object property in file ‘/etc/nagios/mysite/localhost.cfg’ on line 29.

no matter what I do with the host name I get the same result