NRPE and the $USER1$ variable

Question

I have NRPE daemons running on all of my remote Linux boxes. I have a couple configurations in place and I'm trying to standardize the paths in my nrpe.cfg. The changes are deployed via Puppet.

I would like to use the following syntax:

command[mycommand]=$USER1$/check_tcp .. etc.

The $USER1$ variable is not available in my NRPE setup. I could write Puppet templates for all the variants but I would much prefer to manage this through a native method. Is there anything available to do so? If not does anyone have a sample Puppet config that will address this?

Solution 1

I put together a custom Fact that addresses my needs. I also tried a small switch that would apply the arch but it wasn't cross platform.

lib/facter/nrpe.rb

file = File.open("/etc/nagios/resource.cfg" , "r" )
while ( line = file.gets )
  if  /^\$USER1\$=(.*)/ =~ line
    matched="#{$1}"
  end
end
file.close
Facter.add("nrpe") do
  setcode do
    matched
  end
end

Solution 2

I could write Puppet templates for all the variants but I would much prefer to manage this through a native method.

$USERn$ is a standard macro for Nagios. They are defined in the resource.cfg file:

# Sets $USER1$ to be the path to the plugins
$USER1$=/usr/local/nagios/libexec

# Sets $USER2$ to be the path to event handlers
#$USER2$=/usr/local/nagios/libexec/eventhandlers

and this file is included in the main configuration:

# This is an optional resource file that contains $USERx$ macro
# definitions. Multiple resource files can be specified by using
# multiple resource_file definitions.  The CGIs will not attempt to
# read the contents of resource files, so information that is
resource_file=/usr/local/nagios/etc/resource.cfg

AFAIK, you cannot use it on the remote host, with NRPE.

Solution 3

Here are some of the custom facts, and manifest code we use for handling nrpe. Be sure that puppet ensures the service is setup to start at boot, and is running. Since we run Fedora 15, with an older version of puppet, be aware that some versions of puppet can't handle Fedora 15's systemd.

nrpe_plugin_directory.rb

Facter.add("nrpe_plugin_directory") do
    setcode do
            %x{dirs="/usr/lib/nagios/plugins /usr/lib64/nagios/plugins /usr/local/nagios/libexec"; for dir in $dirs; do [[ -e $dir ]] && [[ ! -L $dir ]] && { echo $dir; exit; }; done}.chomp
    end
end

nrpe_cfg_file.rb

Facter.add("nrpe_cfg_file") do
    setcode do
            %x{files="/etc/nagios/nrpe.cfg /usr/local/nagios/etc/nrpe.cfg /usr/local/nagios/nrpe.cfg"; for file in $files; do [[ -f $file ]] && { echo $file; exit; }; done}.chomp
    end
end

Manifest code:

                    file{"/nagios/plugins":
                            ensure => "symlink",
                            target => "${nrpe_plugin_directory}",
                            force => 'true',
                            }

                    file{"$nrpe_plugin_directory":
                            source => "/..../plugins",
                            ensure => "directory",
                            recurse => "true",
                            ignore => ".svn",
                            }
                    case $nrpe_cfg_file {
                            undef: { }
                            default:{
                                    file{"/nagios/nrpe.cfg":
                                            ensure => "symlink",
                                            target => "${nrpe_cfg_file}",
                                            require => File["/nagios"],
                                            }
                                    file{"$nrpe_cfg_file":
                                            source => "/..../nrpe.cfg",
                                            }
            # ..............
                            }

Comments

[becomingwisest]

At my work, we use a custom facts to know where the plugins dir is, and where the cfg is. We also created /nagios, and a symlink /nagios/nrpe.cfg to the actual config file, and /nagios/plugins to the actual plugin dir. Then all commands use /nagios/plugins/...

[Tim Brigham]

That sounds appealing. Could you share the custom fact definition here?

[Tim Brigham]

That's what I figured. I was hoping there was some buried way that the remote NRPE daemon could read the remote resource.cfg file that is installed with the nagios-plugin package. Thanks for the input.