How are unit files loaded in systemd?
Unit File Load Path. Unit files are loaded from a set of paths determined during compilation, described in the two tables below. Unit files found in directories listed earlier override files with the same name in directories lower in the list. When the variable $SYSTEMD_UNIT_PATH is set, the contents of this variable overrides the unit load path.
Can a service take a single argument in systemd?
It is possible for systemd services to take a single argument via the ” [email protected] ” syntax. Such services are called “instantiated” services, while the unit definition without the argument parameter is called a “template”.
Which is the default oneshot in systemd service?
Type=oneshot is the implied default if neither Type= nor ExecStart= are specified. Note that if this option is used without RemainAfterExit= the service will never enter ” active ” unit state, but directly transition from ” activating ” to ” deactivating ” or ” dead ” since no process is configured that shall run continuously.
When does systemd assume the unit to be started?
systemd will assume the unit to be started immediately after the program has begun executing. [Unit] Description=Foo [Service] ExecStart=/usr/sbin/foo-daemon [Install] WantedBy=multi-user.target. Note that systemd assumes here that the process started by systemd will continue running until the service terminates.
How to redirect output of systemd service to a file?
StandardOutput= Controls where file descriptor 1 (STDOUT) of the executed processes is connected to. Takes one of inherit, null, tty, journal, syslog, kmsg, journal+console, syslog+console, kmsg+console or socket. The systemd.exec (5) man page explains other options related to logging.
How to set standardoutput in systemd.exec?
In newer versions of systemd there is a relatively new option ( the github request is from 2016 ish and the enhancement is merged/closed 2017 ish) where you can set the values of StandardOutput or StandardError to file:YOUR_ABSPATH_FILENAME. The file:path option is documented in the most recent systemd.exec man page.
How to add stdout to systemd service file?
The file:path option is documented in the most recent systemd.exec man page. This new feature is relatively new and so is not available for older distros like centos-7 (or any centos before that). I would suggest adding stdout and stderr file in systemd service file itself.