systemd file-hierarchy 7 file-hierarchy systemd file system hierarchy requirements Operating systems using the systemd1 system and service manager are organized based on a file system hierarchy inspired by UNIX, as described in UAPI.9 Linux File System Hierarchy. Additional requirements on when given parts of the hierarchy must be available during boot are listed in Mount Requirements. Many of the paths described here can be queried with the systemd-path1 tool. hier7 File System Hierarchy XDG Base Directory Specification XDG User Directories