Picomon is a very small and minimal alerting tool

Written in Python, it needs at least python 3.2 for the ThreadPools.

On Debian Wheezy the package is python3.

Some checks are implemented using Nagios' checks, available under Debian in package nagios-plugins-basic.

The DNS zone check calls Bortzmeyer's (introduced here).

usage: picomon [-h] [-1] [-D] [-c CONFIG]

optional arguments:
  -h, --help            show this help message and exit
  -1, --one             single run with immediate output of check results
                        (test/debug)
  -D, --debug           Set verbosity to DEBUG
  -c CONFIG, --config CONFIG
                        Set config file (defauts to config.py)

Everything can be configured from config.py: notified email(s), base tick, hosts and checks.

The base_tick option defines the base granularity (in seconds) for polling. Hosts are shorthands to avoid repeating addresses within checks. Checks are then defined as a list of Check-derived class instances that implement every single check (see picomon/checks.py).

Each check may be initialised with some options:

• every: run every every × base_tick seconds;
• retry: number of retries before considering a failure (so failure is after every × (retry+1) × base_tick seconds;
• timeout: subcommand timeout, to avoid stalling checks (defaults to 2 seconds);
• target_name: human-readable name of the target of the check (automatically set by the name option if using Host instances).

In addition some checks have specific options, see picomon/checks.py for examples.

In case you want to check lesser important services and configure very long check intervals, you may want to have another interval, global to all checks, for error retries. This can be set with the error_every option.

For a full list of all available options, see the picomon/init.py file.

Just send the SIGUSR1 signal to the process: it will first print the checks in error state and then the successful checks to the standard output.

Please note that this will cancel the current base_tick sleeping period and thus trigger a new run.

An email can be sent each time a check switches to error state or recovers from an error. These two emails are bound together so that a threading MUA will assemble failure/recovery notifications together.

Picomon can send global reports as a reminder of failed checks. They are sent on a regular basis (configured with option emails.report.every) only if there are some checks in an error state.

You have several solutions :

• Install with distutils, for example: setup.py install --user then run it from your local bin/ directory;
• Run directly with something like python3 -m picomon
• Set python module path by hand: PYTHONPATH=. bin/picomon

The default config file is config.py, so either copy/link the sample one, write your own or use the -c command line argument.

A small watchdog is distributed which will send an email in case the main daemon process exits (OOM, bug, etc.) to the same addresses than those used for check status notifications. You may tune the subject with the config option emails.watchdog_subject.

For now, no sysv initscript / systemd unit / whatever for such a small daemon exists. One simple way to run it is to use something like the following in /etc/rc.local (assuming a standard system-wide install with setup.py install):

for conf in /usr/local/etc/picomon/*.py; do sudo -u nobody picomon-watchdog -c $conf > /tmp/picomon-$(basename $conf .py).log 2>&1 & done

This project is placed under GNU GPLv3. See COPYING.