1.14. Extending the default unit configuration

Procedure

1. Create a configuration directory in /etc/systemd/system/:

   # mkdir /etc/systemd/system/<name>.service.d/

   Replace <name> with the name of the service you want to extend. The syntax applies to all unit types.

2. Create a configuration file with the .conf suffix:

   # touch /etc/systemd/system/name.service.d/<config_name>.conf

   Replace <config_name> with the name of the configuration file. This file adheres to the normal unit file structure and you have to specify all directives in the appropriate sections, see Unit file structure.

   For example, to add a custom dependency, create a configuration file with the following content:

   [Unit]
   Requires=<new_dependency>
   After=<new_dependency>

   The <new_dependency> stands for the unit to be marked as a dependency. Another example is a configuration file that restarts the service after its main process exited, with a delay of 30 seconds:

   [Service]
   Restart=always
   RestartSec=30

   Create small configuration files focused only on one task. Such files can be easily moved or linked to configuration directories of other services.

3. Apply changes to the unit:

   # systemctl daemon-reload
   # systemctl restart <name>.service