Nagios installation worksheet

Afnog 2011 sse

Install the nagios package

pkg_add -r nagios nagios plugins

or failing that do the install using the ports collection from

/usr/ports/net-mgmt/nagios

and

/usr/ports/net-mgmt/nagios plugins

you will be prompted to create new a new group and user account

pw: unknown group `nagios'

You need a "nagios" group.

Would you like me to create it [YES]? yes

Done.

pw: no such user `nagios'

You need a "nagios" user.

Would you like me to create it [YES]? Yes

The following instructions will helpfully be relayed (by the installer) when installation is complete.

Enable Nagios in /etc/rc.conf with the following line:

nagios_enable="YES"

Configuration templates are available in /usr/local/etc/nagios as

*.cfg-sample files. Copy them to *.cfg files where required and

edit to suit your needs. Documentation is available in HTML form

in /usr/local/www/nagios/docs.

If you don't already have a web server running, you will need to

install and configure one to finish off your Nagios installation.

When used with Apache, the following should be sufficient to publish

the web component of Nagios (modify the allow list to suit):

Order deny,allow

Deny from all

Allow from 127.0.0.1

php_flag engine on

php_admin_value open_basedir /usr/local/www/nagios/:/var/spool/nagios/

</Directory>

Options ExecCGI

</Directory>

ScriptAlias /nagios/cgi-bin/ /usr/local/www/nagios/cgi-bin/

Alias /nagios/ /usr/local/www/nagios/

so to deploy an appropriate variation of those instructions we need to do the following.

we need to enable nagios in the /etc/rc.conf, edit that file.

Add the line:

nagios_enable="YES"

We need to add local configuration to apache to point at the nagios instance.

cd /usr/local/etc/apache22/Includes/

Create the new nagios specific configuration for apache.

vi nagios.conf

Add:

Order deny,allow

Deny from all

Allow from 127.0.0.1

Allow from 196.200.216.0/23

php_flag engine on

php_admin_value open_basedir /usr/local/www/nagios/:/var/spool/nagios/

</Directory>

Options ExecCGI

</Directory>

ScriptAlias /nagios/cgi-bin/ /usr/local/www/nagios/cgi-bin/

Alias /nagios/ /usr/local/www/nagios/

Then start apache:

/usr/local/etc/rc.d/apache22 start

rename the sample configuration files in the nagios configuartion directory remove sample from the name you can do this manually or using some shell scripting magic like:

cd /usr/local/etc/nagios

for i in *-sample; do
    cp $i `basename $i -sample`
done

do that also in the objects sub-directory

edit the contacts config file and add the following user

define contact {

contact_name admin

alias Nagios Admin

service_notification_commands notify-service-by-email

host_notification_commands notify-host-by-email

}

we need to edit the cgi.conf in /usr/local/etc/nagios/

Edit `cgi.cfg` and uncomment the following line:

#default_user_name=guest

Change the following lines, adding the word ",guest" at the end of each:

authorized_for_system_information=nagiosadmin,guest
authorized_for_configuration_information=nagiosadmin,guest
authorized_for_all_services=nagiosadmin,guest
authorized_for_all_hosts=nagiosadmin,guest

edit the nagios.cfg
uncomment the line
#cfg_dir=/usr/local/etc/nagios/servers
save the file
create the servers directory
create a configuration file for the measurement of your server
pcXX.cfg
lets measure two services and the availability of the machine.

define host {

host_name 196.200.219.1

alias 196.200.219.1

address 196.200.219.1

contacts admin

max_check_attempts 10

use generic-host

check_command check-host-alive

}

define service {

use generic-service

host_name 196.200.219.1

service_description PING

check_command check_ping!100.0,20%!500.0,60%

check_interval 1

contacts admin

}

define service {

use generic-service

host_name 196.200.219.1

service_description ssh

check_command check_ssh

}

save the file.

Now start the nagios service.

/usr/local/etc/rc.d/nagios start