• rtxn@lemmy.worldM
    8·
    15 hours ago

    Systemd, through the systemctl command, only manages the services. The service itself is defined in a unit file, and it can come from any source, even written manually. The unit file is a text file that describes what the service is, what commands or programs should be executed when it starts or stops (for sshd it’s /usr/bin/sshd -D), what other services or conditions are required (e.g. multi-user.target after the OS has entered multi-user mode), and much more.

    When a package installs a unit file, it will be installed to a subdirectory in /usr/lib/systemd, typically user or system, and when it is enabled, it will be symlinked to a subdirectory in /etc/systemd.

    OpenSSH itself, which provides sshd on most systems, is developed by the OpenBSD team and ported to other OSes by the OpenSSH Portability Team.

    • SEND_BUTTPLUG_PICS@lemmy.zip
      3·
      14 hours ago

      That makes a lot of sense. I actually wrote my own unit files for Jackett and to autostart a virtual machine and moved them into multi-user target wants using the enable command. I guess my thought was that by adding the unit file to systemd it made the program part of systemd in a way but now that I think more about it, saying any of these programs are part of systemd doesn’t actually make sense. Just because sshd came pre-installed with Ubuntu doesn’t make it part of systemd any more than plex is part of systemd.

      Thanks for helping me understand!