How to install Nagios on Debian 11.3

Step 8: Now, start to compile Nagios from sources by issuing the below command

root@linuxhelp:~/nagios-4.4.6# ./configure --with-httpd-conf=/etc/apache2/sites-enabled
checking for a BSD-compatible install... /usr/bin/install -c
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
Creating sample config files in sample-config/ ...
*** Configuration summary for nagios 4.4.6 2020-04-28 ***:
 General Options:
 -------------------------
        Nagios executable:  nagios
        Nagios user/group:  nagios,nagios
       Command user/group:  nagios,nagios
             Event Broker:  yes
        Install ${prefix}:  /usr/local/nagios
    Install ${includedir}:  /usr/local/nagios/include/nagios
                Lock file:  /run/nagios.lock

   Check result directory:  /usr/local/nagios/var/spool/checkresults
           Init directory:  /lib/systemd/system
  Apache conf.d directory:  /etc/apache2/sites-enabled
             Mail program:  /usr/bin/mail
                  Host OS:  linux-gnu
          IOBroker Method:  epoll
 Web Interface Options:
 ------------------------
                 HTML URL:  http://localhost/nagios/
                  CGI URL:  http://localhost/nagios/cgi-bin/
 Traceroute (used by WAP):

Review the options above for accuracy.  If they look okay,
type 'make all' to compile the main program and CGIs.

Step 9: In this step, build Nagios files by issuing the below command.

root@linuxhelp:~/nagios-4.4.6# make all
cd ./base && make
make[1]: Entering directory '/root/nagios-4.4.6/base'

*** Main program, CGIs and HTML files installed ***
You can continue with installing Nagios as follows (type 'make'
without any arguments for a list of all possible options):
make install-init
     - This installs the init script in /lib/systemd/system

  make install-commandmode
     - This installs and configures permissions on the
       directory for holding the external command file

  make install-config
     - This installs sample config files in /usr/local/nagios/etc
make[1]: Leaving directory '/root/nagios-4.4.6'

Step 10: Now, install Nagios binary files, CGI scripts and HTML files by issuing the below command.

root@linuxhelp:~/nagios-4.4.6# make install

Step 11: Next, install Nagios daemon init and external command mode configuration files and make sure you enable Nagios daemon system-wide by using the below command.

root@linuxhelp:~/nagios-4.4.6# make install-init
/usr/bin/install -c -m 755 -d -o root -g root /lib/systemd/system
/usr/bin/install -c -m 755 -o root -g root startup/default-service /lib/systemd/system/nagios.service

root@linuxhelp:~/nagios-4.4.6# make install-commandmode
/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/var/rw
chmod g+s /usr/local/nagios/var/rw

*** External command directory configured ***


root@linuxhelp:~/nagios-4.4.6# systemctl enable nagios.service
Created symlink /etc/systemd/system/multi-user.target.wants/nagios.service → /lib/systemd/system/nagios.service.

Step 12: Next run the Nagios configuration files by using the below command.

root@linuxhelp:~/nagios-4.4.6# make install-config
/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/etc
/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/etc/objects
/usr/bin/install -c -b -m 664 -o nagios -g nagios sample-config/nagios.cfg /usr/local/nagios/etc/nagios.cfg
/usr/bin/install -c -b -m 664 -o nagios -g nagios sample-config/cgi.cfg /usr/local/nagios/etc/cgi.cfg
/usr/bin/install -c -b -m 660 -o nagios -g nagios sample-config/resource.cfg /usr/local/nagios/etc/resource.cfg

*** Config files installed ***

Remember, these are *SAMPLE* config files.  You'll need to read
the documentation for more information on how to actually define
services, hosts, etc. to fit your particular needs.

Step 13: Also, install Nagios configuration file for Apacahe web server, which can be found in /etc/apacahe2/sites-enabled/ directory, by executing the below command.

root@linuxhelp: ~/nagios-4.4.6# make install-webconf
/usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-enabled/nagios.conf

if [ 0 -eq 1]; then \
        ln -s /etc/apache2/sites-enabled/nagios.conf /etc/apache2/sites-enabled/nagios.conf; \
fi
*** Nagios/Apache conf file installed ***

Step 14: Next, create nagiosadmin account and a password by using the below command

root@linuxhelp: ~/nagios-4.4.6# htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
New password:
Re-type new password:
Adding password for user nagiosadmin

Step 15: Enable the nagios cgi services by using the below command.

root@linuxhelp: ~/nagios-4.4.6# a2enmod cgi
Enabling module cgi.
To activate the new configuration, you need to run:
  systemctl restart apache2

Step 16: Next restart, start enable the Nagios service by using the below commands.

root@linuxhelp: ~/nagios-4.4.6# systemctl restart apache2
root@linuxhelp: ~/nagios-4.4.6# systemctl start nagios
root@linuxhelp: ~/nagios-4.4.6# systemctl enable Nagios