NagiosGraph – Graphs in Nagios on CentOS/RHEL 6.3

Nagiosgraph is a Nagios Addon that parses output and performance data from Nagios plugins and stores the data in RRD files. Nagiosgraph creates graphs and generates HTML pages with graphic reports from the data. This tutorial is tested on CentOS/RHEL 6.3, and have following Nagios core and plugin package:

   Nagios Core: nagios-4.0.0
   Nagios Plugin: nagios-plugins-1.4.16

To install Nagios please see my Nagios Installation Docs.

Installation Prerequisite

• Nagios server in working condition.
• We require following packages as well:

   yum -y install perl-GD php-gd rrdtool-perl rrdtool-php rrdtool perl-CGI perl-Time-HiRes

Installation

*) Create a directory where you would download nagios software:

   mkdir /usr/local/src
   cd /usr/local/src

*) Download nagiosgraph package/Untar it and navigate it to that directory

   wget http://downloads.sourceforge.net/project/nagiosgraph/nagiosgraph/1.4.4/nagiosgraph-1.4.4.tar.gz
   tar -xzvf nagiosgraph-1.4.4.tar.gz
   cd nagiosgraph-1.4.4

*) Check for any other Nagiosgraph dependency using "install.pl" script with "check-prereq" options:

   ./install.pl --check-prereq
   checking required PERL modules
     Carp...1.11
     CGI...3.51
     Data::Dumper...2.124
     File::Basename...2.77
     File::Find...1.14
     MIME::Base64...3.08
     POSIX...1.17
     RRDs...1.3008
     Time::HiRes...1.9721
   checking optional PERL modules
     GD...2.44
   checking nagios installation
     found nagios at /usr/local/nagios/bin/nagios
   checking web server installation
     found apache at /usr/sbin/httpd

Note: *) In case any dependency is missing we need to install it using cpan or yum command. *) You need to be root to run this script.

There are two ways to install nagiosgraph either automatically or manually.

1) Automated way which install file and set permission automatically

   ./install.pl --layout overlay --prefix /usr/local/nagios
   checking required PERL modules
     Carp...1.11
     CGI...3.51
     Data::Dumper...2.124
     File::Basename...2.77
     File::Find...1.14
     MIME::Base64...3.08
     POSIX...1.17
     RRDs...1.3008
     Time::HiRes... ***FAIL***
   checking optional PERL modules
     GD...2.44
   checking nagios installation
     found nagios at /usr/local/nagios/bin/nagios
   checking web server installation
     found apache at /usr/sbin/httpd
   Destination directory (prefix)? [/usr/local/nagios] 
   Location of configuration files (etc-dir)? [/usr/local/nagios/etc/nagiosgraph] 
   Location of executables? [/usr/local/nagios/libexec] 
   Location of CGI scripts? [/usr/local/nagios/sbin] 
   Location of documentation (doc-dir)? [/usr/local/nagios/docs/nagiosgraph] 
   Location of examples? [/usr/local/nagios/docs/nagiosgraph/examples] 
   Location of CSS and JavaScript files? [/usr/local/nagios/share] 
   Location of utilities? [/usr/local/nagios/docs/nagiosgraph/util] 
   Location of state files (var-dir)? [/var/nagios] 
   Location of RRD files? [/var/nagios/rrd] 
   Location of log files (log-dir)? [/var/nagios] 
   Path of log file? [/var/nagios/nagiosgraph.log] 
   Path of CGI log file? [/var/nagios/nagiosgraph-cgi.log] 
   URL of CGI scripts? [/nagios/cgi-bin] 
   URL of CSS file? [/nagios/nagiosgraph.css] 
   URL of JavaScript file? [/nagios/nagiosgraph.js] 
   Path of Nagios performance data file? [/tmp/perfdata.log] 
   URL of Nagios CGI scripts? [/nagios/cgi-bin] 
   username or userid of Nagios user? [nagios] 
   username or userid of web server user? [apache] 
   Modify the Nagios configuration? [n] 
   Modify the Apache configuration? [n] 
   configuration:
     ng_layout            overlay
     ng_prefix            /usr/local/nagios
     ng_etc_dir           /usr/local/nagios/etc/nagiosgraph
     ng_bin_dir           /usr/local/nagios/libexec
     ng_cgi_dir           /usr/local/nagios/sbin
     ng_doc_dir           /usr/local/nagios/docs/nagiosgraph
     ng_examples_dir      /usr/local/nagios/docs/nagiosgraph/examples
     ng_www_dir           /usr/local/nagios/share
     ng_util_dir          /usr/local/nagios/docs/nagiosgraph/util
     ng_var_dir           /var/nagios
     ng_rrd_dir           /var/nagios/rrd
     ng_log_dir           /var/nagios
     ng_log_file          /var/nagios/nagiosgraph.log
     ng_cgilog_file       /var/nagios/nagiosgraph-cgi.log
     ng_url               /nagios
     ng_cgi_url           /nagios/cgi-bin
     ng_css_url           /nagios/nagiosgraph.css
     ng_js_url            /nagios/nagiosgraph.js
     nagios_cgi_url       /nagios/cgi-bin
     nagios_perfdata_file /tmp/perfdata.log
     nagios_user          nagios
     www_user             apache
     modify_nagios_config n
     nagios_config_file   /usr/local/nagios/etc/nagios.cfg
     nagios_commands_file /usr/local/nagios/var/rw/nagios.cmd 
     modify_apache_config n
     apache_config_dir    /etc/httpd/conf.d
     apache_config_file   
   Continue with this configuration? [y] 

OR

2) Manual steps to install Nagiosgraph.

2.1) Create NagiosGraph directory and copy its configuration file in it:

   mkdir /usr/local/nagios/etc/nagiosgraph
   cp -vr etc /usr/local/nagios/etc/nagiosgraph/

2.2) Change NagiosGraph path in cgi and perl scripts:

   sed -i "s#/opt/nagiosgraph/etc#/usr/local/nagios/etc/nagiosgraph/#g" cgi/*cgi 
   sed -i "s#/opt/nagiosgraph/etc#/usr/local/nagios/etc/nagiosgraph/#g" lib/insert.pl

2.3) Copy cgi scripts to nagios appropriate directory that will be served by the web-server:

   cp cgi/*.cgi /usr/local/nagios/sbin

2.4) Copy insert.pl to nagios appropriate directory from which it can be executed:

   cp lib/insert.pl /usr/local/nagios/libexec

2.5) Copy CSS and JavaScript files to a nagios directory that would be served by the web server:

   cp share/nagiosgraph.css /usr/local/nagios/share
   cp share/nagiosgraph.js /usr/local/nagios/share

2.6) In NagiosGraph SSI file, set the URL for nagiosgraph.js,copy it to its appropriate location:

   vi share/nagiosgraph.ssi
   src="/nagiosgraph/nagiosgraph.js"   to    src="/nagios/nagiosgraph.js"

   cp share/nagiosgraph.ssi /usr/local/nagios/share/ssi/common-header.ssi

2.7) Replace the Nagios action icon with the nagiosgraph graph icon:

   cp share/graph.gif /usr/local/nagios/share/images/action.gif

Configuration

Edit Nagiosgraph configuration file and set at least the following parameters:

   vi /usr/local/nagios/etc/nagiosgraph/nagiosgraph.conf
    perflog           = /usr/local/nagios/var/perfdata.log
    rrddir            = /usr/local/nagios/var/rrd
    mapfile           = /usr/local/nagios/etc/nagiosgraph/map
    nagiosgraphcgiurl = /nagios/cgi-bin
    javascript        = /nagios/nagiosgraph.js
    stylesheet        = /nagios/nagiosgraph.css
    logfile           = /usr/local/nagios/var/nagiosgraph.log
    cgilogfile        = /usr/local/nagios/var/nagiosgraph-cgi.log

Creating necessary directory and fixing the permissions

Changing the ownership of conf and other necessary file that we have copyied earlier

   chown nagios:nagios /usr/local/nagios/etc/nagiosgraph
   chown nagios:nagios /usr/local/nagios/sbin
   chown nagios:nagios /usr/local/nagios/libexec/insert.pl
   chown nagios:nagios /usr/local/nagios/share/nagiosgraph.css  /usr/local/nagios/share/nagiosgraph.js
   chown nagios:nagios /usr/local/nagios/share/ssi/common-header.ssi

Created RRD directory and set permission of "rrddir" to be writable by *nagios* user and read by *apache* (webserver user).

   mkdir /usr/local/nagios/var/rrd
   chmod nagios:apache /usr/local/nagios/var/rrd
   chmod 755 /usr/local/nagios/var/rrd

Set writeable permissions to user *nagios* for “logfile” config directive:

   touch /usr/local/nagios/var/nagiosgraph.log
   chown nagios /usr/local/nagios/var/nagiosgraph.log
   chmod 644 /usr/local/nagios/var/nagiosgraph.log

Set writeable permissions to user *apache* for “cgilogfile” config directive:

   touch /usr/local/nagios/var/nagiosgraph-cgi.log
   chown apache /usr/local/nagios/var/nagiosgraph-cgi.log
   chmod 644 /usr/local/nagios/var/nagiosgraph-cgi.log

Make sure that the *nagios* user can create and delete perfdata files:

Nagios Configuration

Add the following line at the end of Nagios configuration file:

   vi /usr/local/nagios/etc/nagios.cfg

   # begin nagiosgraph configuration
   # process nagios performance data using nagiosgraph
   process_performance_data=1
   service_perfdata_file=/tmp/perfdata.log
   service_perfdata_file_template=$LASTSERVICECHECK$||$HOSTNAME$||$SERVICEDESC$||$SERVICEOUTPUT$||$SERVICEPERFDATA$
   service_perfdata_file_mode=a
   service_perfdata_file_processing_interval=30
   service_perfdata_file_processing_command=process-service-perfdata-for-nagiosgraph
   # end nagiosgraph configuration

In the Nagios commands file (commands.cfg) define the process-service-perfdata command at the end:

   vi /usr/local/nagios/etc/objects/commands.cfg
   # command to process nagios performance data for nagiosgraph
   define command {
      command_name process-service-perfdata-for-nagiosgraph
      command_line /usr/local/nagios/libexec/insert.pl
   }

Modify the Nagios sidebar (e.g. /usr/local/nagios/share/side.php) by inserting bullets under the 'Trends' heading:

<li><a href="<?php echo $cfg["cgi_base_url"];?>/trends.cgi" target="<?php echo $link_target;?>">Trends</a>
<ul>
<li><a href="<?php echo $cfg["cgi_base_url"];?>/show.cgi" target="<?php echo $link_target;?>">Graphs</a></li>

<li><a href="<?php echo $cfg["cgi_base_url"];?>/showhost.cgi" target="<?php echo $link_target;?>">Graphs by Host</a></li>
<li><a href="<?php echo $cfg["cgi_base_url"];?>/showservice.cgi" target="<?php echo $link_target;?>">Graphs by Service</a></li>

<li><a href="<?php echo $cfg["cgi_base_url"];?>/showgroup.cgi" target="<?php echo $link_target;?>">Graphs by Group</a></li>
</ul>
</li>

Validation and testing.

Verify Nagios configuration and restart it once every thing is ok

   /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
   /etc/init.d/nagios restart

Verify that nagiosgraph configuration is working by running showconfig.cgi:

   http://localhost/nagios/cgi-bin/showconfig.cgi
    OR 
http://Server-IP-Address/nagios/cgi-bin/showconfig.cgi

If everything is working up to this point, try graphing some data by running show.cgi:

   http://localhost/nagios/cgi-bin/show.cgi
    OR 
http://Server-IP-Address/nagios/cgi-bin/show.cgi

Note: If you get a 500 internal error and the issue is with Apache. If you get a “no rrd data found” error, then the configuration of nagiosgraph is incorrect.

To test if you configuration is working you can try to run the script directly:

   cd /usr/local/nagios/libexec
   ./insert.pl

To verify that there is some data in the RRD directory:

   ls /var/nagios/rrd/
   web001    web002 app001 app002 db001 db002

Adding Service to NagiosGraph

Now we need to define an action URL for the services that we want to graph, so that you can click to go directly to the graphs for that service from the Nagios Core web interface.

   define service {
      name  graphed-service
      action_url /nagiosgraph/cgi-bin/show.cgi?host=$HOSTNAME$&service=$SERVICEDESC$' onMouseOver='showGraphPopup(this)' onMouseOut='hideGraphPopup()' rel='/nagiosgraph/cgi-bin/showgraph.cgi?host=$HOSTNAME$&service=$SERVICEDESC$&period=week&rrdopts=-w+450+-j
    }

Then, you can have the services you want graphed inherit from it, as well as from any other templates they use, by adding "graphed-service" to the value for the use directive:

   define service {
 use generic-service,graphed-service
 host_name web001
 service_description PING
 check_command check_ping!100,10%!200,20%
}

You should do this for all the services for which you want graphing.

Validate the configuration file and reload the Nagios Core server once again:

   /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
   /etc/init.d/nagios reload

With this done, visiting the Service section of the web interface should include action icons after each graphed service.