pynagioscheck is a Python framework for Nagios plug-in developers.
pynagioscheck strives to conform to the practices described in the
Nagios Plug-in Development Guidelines_ and, more importantly, save
valuable system administrator time.
.. _Nagios Plug-in Development Guidelines: http://nagiosplug.sourceforge.net/developer-guidelines.html
Check examples/ for a jump start.
The long version:
1. Subclass ``nagioscheck.NagiosCheck`` as ``YourCheck``.
#. Set ``YourCheck.version``. I prefer the ``major.minor.patch``
format, but you can use whatever you like. Increment this
version number with every revision to your check script.
#. If your check script takes mandatory arguments, describe them in
``YourCheck.usage``. Arguments are not the same as options.
e.g.::
YourCheck.usage = '[options] HOST PORT'
#. From ``YourCheck.__init__()``, invoke ``NagiosCheck.__init__(self)``
before you do anything else.
#. Let ``NagiosCheck`` know about any optional arguments you might
want to parse with ``NagiosCheck.add_option()``. It makes the most
sense to do this from inside ``YourCheck.__init__()``.
#. Define a ``YourCheck.check()`` method that will implement your
actual service check. This method takes two arguments:
a. ``opts``: An instance of ``optparse.Values``.
Suppose an option is registered with::
self.add_option('H', 'host', 'host', 'Hostname or ...')
then, if the user supplies a hostname with ``-H HOST`` or
``--host HOST`` at the command line, the option argument
(``HOST``) will be available from inside the ``check()`` method
as::
host = getattr(opts, 'host')
Option argument attributes will be ``None`` if the option was
not supplied at the command line.
#. ``args``: A list of mandatory postitional arguments. This list
should match the usage information in ``YourCheck.usage``.
``YourCheck.check()`` *must* raise ``nagioscheck.Status`` as soon as
the result of the service check is known. ``YourCheck.check()``
*must not* return. See the examples and source for details.
#. With ``YourCheck`` defined, instantiate and make it go with::
if __name__ == '__main__':
YourCheck().run() - Output string formatting and exit statuses conform to Nagios
plug-in development guidelines. You don't need to remember that
exit status 2 is used to signal CRITICAL check status, or that
there are twelve inches in a foot.
- Routines that make it easier to report Nagios perfdata
(performance data).
- A handful of utility functions for common data mangling and
presentation chores.
- A way to clean up after yourself if your execution time limit
expires. This feature may not work with older versions of the
Nagios NRPE server::
--- nagios-nrpe-2.12~/src/nrpe.c 2008-03-11 08:04:43.000000000 +1100
+++ nagios-nrpe-2.12/src/nrpe.c 2011-05-11 23:01:06.182404333 +1000
@@ -1467,6 +1467,7 @@
/* send termination signal to child process group */
kill((pid_t)(-pid),SIGTERM);
+ sleep(5); /* or whatever */
kill((pid_t)(-pid),SIGKILL);
}
See ``NagiosCheck.expired()`` for details.
- ``-v`` works out of the box. Supply it more than once for
additional verbosity. There are four levels in total. You
control what is output at each level with your arguments to
``nagioscheck.Status()``. See the examples and source for
details. Use ``-vvv`` to view a backtrace of your check script to
the point where it raised ``NagiosCheck.Status``::
% check_redis -vvv
CRITICAL: Error 61 connecting 127.0.0.1:6379. Connection refused.
File "./check_redis", line 29, in check
info = r.info()
File "build/bdist.macosx-10.6-universal/egg/redis/client.py", line 380, in info
return self.execute_command('INFO')
[...]
- ``-h`` and ``--help`` work out of the box.
- ``--version`` works out of the box.- Validation helpers.
- Threshold helpers.Saj Goonatilleke sg@redu.cx