The timer runs every 15 minutes by default; edit journal-monitor.timer before installing to change this.

Install by specifying the recipients of the monitoring emails, a priority level (emerg, alert, crit, err, warning, notice, info, or debug), and the systemd units to monitor. Multiple recipients need single quotes around the comma-separated list:

sudo ./install '[email protected], [email protected]' warning unit1 unit2

Service messages written to stderr are logged to the systemd journal at the info level by default. To log messages at a different priority level, prefix the log messages with <n> where n is the numeric code for a log level (0 for emerg, 7 for debug).

Then start the timer:

sudo systemctl start journal-monitor.timer

You can check that the timer loaded properly:

systemctl list-timers

If you want the timer to be enabled at bootup:

sudo systemctl enable journal-monitor.timer

You can launch a single run of the journal monitor manually:

sudo systemctl start journal-monitor

The test directory contains a simple service (fail.service) that does nothing but write to stderr, which can be used for testing the journal monitor. The test service logs to the journal at the warning (4) level.