Adding Graphs to Nagios Using pnp4nagios

This post will go over how to add graphs to nagios using the pnp4nagios plugin.

Step 1:
Install and/or compile the necessary applications.  pnp4nagios was installed as part of the command "yum install nagios*" performed in a previous post.

rpm -q pnp4nagios
pnp4nagios-0.6.20-1.el6.i686

Step 2:
Configure the pnp4nagios commands.  Since this is a small installation with only a few hosts being monitored, most of the defaults will be used.  However, the commands still need to be added to the nagios configuration:

define command {
command_name    process-service-perfdata-file
command_line    /usr/libexec/pnp4nagios/process_perfdata.pl --bulk=/tmp/service-perfdata
}

define command {
command_name    process-host-perfdata-file
command_line    /usr/libexec/pnp4nagios/process_perfdata.pl --bulk=/tmp/host-perfdata
}

Step 3:
Modify nagios.cfg.  The diff with the original cfg is shown below.

diff nagios.cfg nagios.cfg.bak
834,835c834
< 
< process_performance_data=1
---
> process_performance_data=0
857,858c856,857
< host_perfdata_file=/tmp/host-perfdata
< service_perfdata_file=/tmp/service-perfdata
---
> #host_perfdata_file=/tmp/host-perfdata
> #service_perfdata_file=/tmp/service-perfdata
872,873d870
< host_perfdata_file_template=DATATYPE::HOSTPERFDATA\tTIMET::$TIMET$\tHOSTNAME::$HOSTNAME$
\tHOSTPERFDATA::$HOSTPERFDATA$\tHOSTCHECKCOMMAND::$HOSTCHECKCOMMAND$\tHOSTSTATE::$HOSTSTATE$
\tHOSTSTATETYPE::$HOSTSTATETYPE$\tHOSTOUTPUT::$HOSTOUTPUT$
< service_perfdata_file_template=DATATYPE::SERVICEPERFDATA\tTIMET::$TIMET$\tHOSTNAME::$HOSTNAME$
\tSERVICEDESC::$SERVICEDESC$\tSERVICEPERFDATA::$SERVICEPERFDATA$\tSERVICECHECKCOMMAND::$SERVICECHECKCOMMAND$
\tHOSTSTATE::$HOSTSTATE$\tHOSTSTATETYPE::$HOSTSTATETYPE$\tSERVICESTATE::$SERVICESTATE$
\tSERVICESTATETYPE::$SERVICESTATETYPE$\tSERVICEOUTPUT::$SERVICEOUTPUT$
887,888d883
< host_perfdata_file_mode=a
< service_perfdata_file_mode=a
900,901d894
< host_perfdata_file_processing_interval=15
< service_perfdata_file_processing_interval=15
912,913d904
< host_perfdata_file_processing_command=process-host-perfdata-file
< service_perfdata_file_processing_command=process-service-perfdata-file

Step 4:
Restart nagios and verify the page shows up at http://<nagiosip>/pnp4nagios/

Step 5:
Add extended info in nagios to create links to graphs of the applicable host and service.  Add to templates.cfg:

define host {
name            host-pnp
action_url      /pnp4nagios/index.php/graph?host=$HOSTNAME$&srv=_HOST_
register        0
}

define service {
name            service-pnp
action_url      /pnp4nagios/index.php/graph?host=$HOSTNAME$&srv=$SERVICEDESC$
register        0
}

Then add these new templates to the desired host and service definitions.  For example:

define host{
        use                     linux-server,host-pnp
        host_name               puppetmaster
        alias                   puppetmaster
        address                 192.168.1.15
}

define service{
        use generic-service,service-pnp
        host_name puppetmaster
        service_description PING
        check_command check_ping!100.0,20%!500.0,60%
}

Step 6:
Verify functionality.  Note the new graph icons available for the host/services.

Clicking on the icons gives links to the desired rrd graphs.  For example, the custom crond check shows the process has been running as desired.

pnp4nagios can also print out a nicely formatted report of the desired services/hosts to a pdf.