Changes

Units are configured by ''systemd'' using configuration files that can be found in different directories. Each of them has different priority and behaviour:

This directory stores a copy of configuration files. This is the default destination for new installed configuration file. Typically files in this directory should not be modified by the user.

This is the directory where to store a new ''Unit'' or to modify an existing one. The files present in this directory have the highest priority.

The files present in this directory have higher priority only respect the ones on <code>/lib/systemd/system</code>. Systemd creates these configuration files dinamically at runtime; modification on this directory can be used for testing a runtime behaviour for a ''Unit'' but all modifications will be lost at next boot.