- systemd will warn you during boot if /usr is on a different
- file system than /. While in systemd itself very little will
- break if /usr is on a separate partition, many of its
- dependencies very likely will break sooner or later in one
- form or another. For example, udev rules tend to refer to
- binaries in /usr, binaries that link to libraries in /usr or
- binaries that refer to data files in /usr. Since these
- breakages are not always directly visible, systemd will warn
- about this, since this kind of file system setup is not really
- supported anymore by the basic set of Linux OS components.
+ systemd will warn during early boot if /usr is not already mounted at
+ this point (that means: either located on the same file system as / or
+ already mounted in the initrd). While in systemd itself very little
+ will break if /usr is on a separate, late-mounted partition, many of
+ its dependencies very likely will break sooner or later in one form or
+ another. For example, udev rules tend to refer to binaries in /usr,
+ binaries that link to libraries in /usr or binaries that refer to data
+ files in /usr. Since these breakages are not always directly visible,
+ systemd will warn about this, since this kind of file system setup is
+ not really supported anymore by the basic set of Linux OS components.