How to install Nagios with Nginx on CentOS

Install the necessary tools which is to be used for Nagios.

[root@nagios nagios]# yum groupinstall ' Development Tools'  -y
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Group Process
Loading mirror speeds from cached hostfile
 * base: centos-hcm.viettelidc.com.vn
 * epel: ftp.jaist.ac.jp
 * extras: mirrors.vonline.vn
 * updates: mirrors.aluhost.com
base/group_gz                                                                                                                                                                                | 226 kB     00:00    
epel/group_gz                                                                                                                                                                                | 150 kB     00:00    
Package gcc-4.4.7-18.el6.x86_64 already installed and latest version
Package 1:make-3.81-23.el6.x86_64 already installed and latest version
Package patch-2.6-6.el6.x86_64 already installed and latest version
Package 1:pkgconfig-0.23-9.1.el6.x86_64 already installed and latest version
Package gettext-0.17-18.el6.x86_64 already installed and latest version
Package elfutils-0.164-2.el6.x86_64 already installed and latest version
Package cvs-1.11.23-16.el6.x86_64 already installed and latest version
Resolving Dependencies
-->  Running transaction check
--->  Package autoconf.noarch 0:2.63-5.1.el6 will be installed
--->  Package automake.noarch 0:1.11.1-4.el6 will be installed
--->  Package binutils.x86_64 0:2.20.51.0.2-5.44.el6 will be updated
--->  Package binutils.x86_64 0:2.20.51.0.2-5.47.el6_9.1 will be an update
--->  Package bison.x86_64 0:2.4.1-5.el6 will be installed
--->  Package byacc.x86_64 0:1.9.20070509-7.el6 will be installed
--->  Package cscope.x86_64 0:15.6-7.el6 will be installed
--->  Package ctags.x86_64 0:5.8-2.el6 will be installed
.
.
.
Dependency Updated:
  libstdc++.x86_64 0:4.4.7-18.el6                         perl.x86_64 4:5.10.1-144.el6                        perl-CGI.x86_64 0:3.51-144.el6                 perl-ExtUtils-MakeMaker.x86_64 0:6.55-144.el6       
  perl-ExtUtils-ParseXS.x86_64 1:2.2003.0-144.el6         perl-Module-Pluggable.x86_64 1:3.90-144.el6         perl-Pod-Escapes.x86_64 1:1.04-144.el6         perl-Pod-Simple.x86_64 1:3.13-144.el6               
  perl-Test-Harness.x86_64 0:3.17-144.el6                 perl-Test-Simple.x86_64 0:0.92-144.el6              perl-devel.x86_64 4:5.10.1-144.el6             perl-libs.x86_64 4:5.10.1-144.el6                   
  perl-version.x86_64 3:0.77-144.el6                      systemtap-runtime.x86_64 0:2.9-7.el6              
Complete!

Next create a new Nginx configuration for Nagios under the name of conf.d directory as shown below. Enter the following contents into the file and save it.

[root@nagios ~]# vim /etc/nginx/conf.d/nagios.conf
server {
 listen 80 
 server_name nagios_local 
 access_log /var/log/nginx/nagios-access.log 
 error_log /var/log/nginx/nagios-error.log info 
 root /usr/local/nagios/share 
 index index.php 
 auth_basic " Nagios Restricted Access"  
 auth_basic_user_file /usr/local/nagios/passwd 
 location /data-stylesheets {
 alias /usr/local/nagios/share/data-stylesheets 
 }
 location ~ .cgi$ {
     root /usr/local/nagios/sbin/ 
     include fastcgi_params 
     rewrite ^/nagios/cgi-bin/(.*).cgi /$1.cgi break 
     fastcgi_param AUTH_USER $remote_user 
     fastcgi_param REMOTE_USER $remote_user 
     fastcgi_pass unix:/var/run/fcgiwrap.socket 
     fastcgi_param SCRIPT_FILENAME /usr/local/nagios/sbin/$fastcgi_script_name 
     fastcgi_param PATH_INFO $fastcgi_script_name 
 }
 location ~ .php$ {
    include fastcgi_params 
    fastcgi_pass unix:/var/run/php-fpm/nagios.socket 
    fastcgi_index index.php 
    fastcgi_param SCRIPT_FILENAME /usr/local/nagios/share$fastcgi_script_name 
   fastcgi_param PATH_INFO $fastcgi_script_name 
 }
 location ~ (.*.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf))$ {
    root /usr/local/nagios/share/ 
    rewrite ^/nagios/(.*) /$1 break 
    access_log off  expires max 
 }
}

Rename the Nginx default configuration by executing the following command.

[root@nagios ~]# mv /etc/nginx/conf.d/default.conf /etc/nginx/conf.d/default.conf.old

Next restart and enable the Nginx service by running the following commands

[root@nagios ~]# service nginx start
Starting nginx:                                            [  OK  ]
[root@nagios ~]# chkconfig nginx on

Open HTTP port (80) on iptables by running the commands.

[root@nagios ~]# iptables -A INPUT -p tcp --dport 80 -j ACCEPT
[root@nagios ~]# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[  OK  ]

Now configure PHP-FPM for Nagios by executing the vim editor along with the Nagios configuration file. Enter the following contents in the file.

[root@nagios ~]# vim /etc/php-fpm.d/nagios.conf

[nagios]
 listen = 127.0.0.1:9000
listen  /var/run/php-fpm/nagios.socket
listen.owner = nginx
listen.group = nginx
listen.mode=0660listen.allowed_clients = 127.0.0.1

user = nagios
group = nagios
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35

 request_slowlog_timeout = 0
slowlog = /var/log/php-fpm/www-slow.log

 php_admin_value[sendmail_path] = /usr/sbin/sendmail -t -i -f www@my.domain.com
php_flag[display_errors] = on
php_admin_value[error_log] = /var/log/php-fpm/nagios-error.log
php_admin_flag[log_errors] = on
 php_admin_value[memory_limit] = 128M
php_value[session.save_handler] = files
php_value[session.save_path] = /var/lib/php/session

Now start the PHP-FPM service by running the following command.

[root@nagios ~]# service php-fpm start
Starting php-fpm: [14-Jul-2017 16:07:48] ERROR: [pool nagios] cannot get uid for user ' nagios' 
[14-Jul-2017 16:07:48] ERROR: FPM initialization failed
                                                           [FAILED]

You will get error like shown above, because the Nagios user was not created yet. So create a new user for Nagios by executing the following commands.

[root@nagios ~]# useradd nagios
[root@nagios ~]# usermod -G nagios nginx

Now start and enable PHP-FPM service by running the following commands.

[root@nagios ~]# service php-fpm start
Starting php-fpm:                                          [  OK  ]
[root@nagios ~]# chkconfig php-fpm on

Next download the latest Nagios tarball package from its official website and then extract it by running the tar command followed by the downloaded package.

[root@nagios ~]# tar -xzf nagios-4.3.2.tar.gz

Now compile and install Nagios using the below command.

[root@nagios ~]# cd nagios-4* & &  ./configure & &  make all & &  make install & &  make install-init & &  make install-config & &  make install-commandmode & &  make install-webconf
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
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables...
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether make sets $(MAKE)... yes
checking whether ln -s works... yes
checking for strip... /usr/bin/strip
checking how to run the C preprocessor... gcc -E
.
.
.
/usr/bin/install -c -b -m 664 -o nagios -g nagios sample-config/template-object/printer.cfg /usr/local/nagios/etc/objects/printer.cfg
/usr/bin/install -c -b -m 664 -o nagios -g nagios sample-config/template-object/switch.cfg /usr/local/nagios/etc/objects/switch.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.

/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 ***

/usr/bin/install -c -m 644 sample-config/httpd.conf /etc/httpd/conf.d/nagios.conf
if [ 0 -eq 1 ]  then 
                        ln -s /etc/httpd/conf.d/nagios.conf /etc/apache2/sites-enabled/nagios.conf  
            fi
*** Nagios/Apache conf file installed ***

If some error occurs while using make or make install command, try after installing gcc and glibc package through yum command.

Verify the Nagios configuration by running the following command.

[root@nagios nagios-4.3.2]# /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
Nagios Core 4.3.2
Copyright (c) 2009-present Nagios Core Development Team and Community Contributors
Copyright (c) 1999-2009 Ethan Galstad
Last Modified: 2017-05-09
License: GPL
Website: https://www.nagios.org
Reading configuration data...
   Read main config file okay...
   Read object config files okay...

Running pre-flight check on configuration data...
Checking objects...
            Checked 8 services.
            Checked 1 hosts.
            Checked 1 host groups.
            Checked 0 service groups.
            Checked 1 contacts.
            Checked 1 contact groups.
            Checked 24 commands.
            Checked 5 time periods.
            Checked 0 host escalations.
            Checked 0 service escalations.
Checking for circular paths...
            Checked 1 hosts
            Checked 0 service dependencies
            Checked 0 host dependencies
            Checked 5 timeperiods
Checking global event handlers...
Checking obsessive compulsive processor commands...
Checking misc settings...

Total Warnings: 0
Total Errors:   0
Things look okay - No serious problems were detected during the pre-flight check

Next install the required Nagios plugins and press y to continue with the installation process.

[root@nagios ~]# yum install nagios-plugins-all -y
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Install Process
Loading mirror speeds from cached hostfile
 * base: centos-hcm.viettelidc.com.vn
 * epel: ftp.jaist.ac.jp
 * extras: mirrors.vonline.vn
 * updates: mirrors.aluhost.com
Resolving Dependencies
-->  Running transaction check
--->  Package nagios-plugins-all.x86_64 0:2.2.1-1.el6 will be installed
-->  Processing Dependency: nagios-plugins-wave for package: nagios-plugins-all-2.2.1-1.el6.x86_64
-->  Processing Dependency: nagios-plugins-users for package: nagios-plugins-all-2.2.1-1.el6.x86_64
-->  Processing Dependency: nagios-plugins-ups for package: nagios-plugins-all-2.2.1-1.el6.x86_64
-->  Processing Dependency: nagios-plugins-time for package: nagios-plugins-all-2.2.1-1.el6.x86_64
-->  Processing Dependency: nagios-plugins-tcp for package: nagios-plugins-all-2.2.1-1.el6.x86_64
-->  Processing Dependency: nagios-plugins-swap for package: nagios-plugins-all-2.2.1-1.el6.x86_64
.
.
.
-1.el6             nagios-plugins-swap.x86_64 0:2.2.1-1.el6            nagios-plugins-tcp.x86_64 0:2.2.1-1.el6           
  nagios-plugins-time.x86_64 0:2.2.1-1.el6             nagios-plugins-ups.x86_64 0:2.2.1-1.el6             nagios-plugins-users.x86_64 0:2.2.1-1.el6           nagios-plugins-wave.x86_64 0:2.2.1-1.el6          
  net-snmp-utils.x86_64 1:5.5-60.el6                   postgresql-libs.x86_64 0:8.4.20-7.el6               qstat.x86_64 0:2.11-9.20080912svn311.el6          
Complete!

Follow the below steps to create softlink for Nagios plugins, before that remove the default contents of libexec. Now change the ownership permissions for those plugin directories.

[root@nagios ~]# rm -rf /usr/local/nagios/libexec
[root@nagios ~]# ln -s /usr/lib64/nagios/plugins /usr/local/nagios/libexec
[root@nagios ~]# chown -R nagios:nagios /usr/local/nagios/libexec

Start and enable nagios service by running the following command.

[root@nagios ~]# service nagios start
Starting nagios: done.
[root@nagios ~]# chkconfig nagios on

Create password for nagiosadmin user and enter the required password for the admin user.

[root@nagios ~]# htpasswd -c /usr/local/nagios/passwd nagiosadmin
New password:
Re-type new password:
Adding password for user nagiosadmin

Next create softlink as shown below by creating a directory and running the following commands.

[root@nagios ~]# mkdir /usr/local/nagios/share/nagios
[root@nagios ~]# cd /usr/local/nagios/share/nagios/
[root@nagios nagios]# ln -s /usr/local/nagios/share/data-stylesheets/ data-stylesheets
[root@nagios nagios]# ln -s /usr/local/nagios/share/js js

Install the spawn-fcgi for the Nagios and press y to continue with the installation procedure.

[root@nagios nagios]# yum install fcgi-devel spawn-fcgi -y
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Install Process
Loading mirror speeds from cached hostfile
 * base: centos-hcm.viettelidc.com.vn
 * epel: ftp.jaist.ac.jp
 * extras: mirrors.vonline.vn
 * updates: mirrors.aluhost.com
Resolving Dependencies
-->  Running transaction check
--->  Package fcgi-devel.x86_64 0:2.4.0-12.el6 will be installed
-->  Processing Dependency: fcgi = 2.4.0-12.el6 for package: fcgi-devel-2.4.0-12.el6.x86_64
-->  Processing Dependency: libfcgi.so.0()(64bit) for package: fcgi-devel-2.4.0-12.el6.x86_64
-->  Processing Dependency: libfcgi++.so.0()(64bit) for package: fcgi-devel-2.4.0-12.el6.x86_64
--->  Package spawn-fcgi.x86_64 0:1.6.3-1.el6 will be installed
-->  Running transaction check
--->  Package fcgi.x86_64 0:2.4.0-12.el6 will be installed
-->  Finished Dependency Resolution
.
.
.
Installed:
  fcgi-devel.x86_64 0:2.4.0-12.el6                                                                          spawn-fcgi.x86_64 0:1.6.3-1.el6                                                                         
Dependency Installed:
  fcgi.x86_64 0:2.4.0-12.el6                                                                                                                                                                                       

Complete!

Next download the fcgiwrap and compile it by executing the following command.

[root@nagios nagios]# cd /usr/local/src/ & &  git clone https://github.com/gnosek/fcgiwrap.git & &  cd fcgiwrap & &  autoreconf -i & &  ./configure & &  make & &  make install
Initialized empty Git repository in /usr/local/src/fcgiwrap/.git
remote: Counting objects: 270, done.
remote: Total 270 (delta 0), reused 0 (delta 0), pack-reused 270
Receiving objects: 100% (270/270), 63.35 KiB | 60 KiB/s, done.
Resolving deltas: 100% (139/139), done.
checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking for pkg-config... /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0... yes
checking for FCGX_Init in -lfcgi... yes
checking for systemd... no
checking how to run the C preprocessor... gcc -E
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
.
.
.
config.status: creating Makefile
config.status: creating config.h
cc -std=gnu99 -Wall -Wextra -Werror -pedantic -O2 -g3    fcgiwrap.c  -lfcgi  -o fcgiwrap
install -d -m 755 /usr/local/sbin
install -m 755 fcgiwrap /usr/local/sbin
install -d -m 755 /usr/local/man/man8
install -m 644 fcgiwrap.8 /usr/local/man/man8

Now edit the spawn-fcgi configuration using the vim editor and enter the following contents into the file.

[root@nagios ~]# vim /etc/sysconfig/spawn-fcgi

FCGI_SOCKET=/var/run/fcgiwrap.socket
FCGI_PROGRAM=/usr/local/sbin/fcgiwrap
FCGI_USER=nginx
FCGI_GROUP=nginx
FCGI_EXTRA_OPTIONS=" -M 0700" 
OPTIONS=" -u $FCGI_USER -g $FCGI_GROUP -s $FCGI_SOCKET -S $FCGI_EXTRA_OPTIONS -F 1 -P /var/run/spawn-fcgi.pid -- $FCGI_PROGRAM" 

[root@nagios ~]# service spawn-fcgi start
Starting spawn-fcgi:                                       [  OK  ]
[root@nagios ~]# chkconfig spawn-fcgi on