Mengapa unit pengguna systemd saya tidak mulai saat boot?

Saya mencoba membuat unit pengguna systemd dan memulainya ketika sistem melakukan boot. Layanan memang mulai secara manual, namun tidak dimulai saat boot.

Dari pencarian di Internet saya belajar bahwa agar unit pengguna untuk memulai saat boot, saya seharusnya perlu menjalankan loginctl enable-linger <username>, tetapi ini tampaknya tidak berpengaruh sama sekali. Memang, halaman manual mengatakan:

       Enable/disable user lingering for one or more users. If enabled for
       a specific user, a user manager is spawned for the user at boot and
       kept around after logouts. This allows users who are not logged in
       to run long-running services.

Meskipun menjalankan perintah ini, layanan saya tidak mulai saat boot.

loginctl enable-linger error

Unit:

$ cat ~/.config/systemd/user/thin\@.service
[Unit]
Description=A fast and very simple Ruby web server

[Service]
Type=simple
EnvironmentFile=/home/error/.config/thin/%i
ExecStart=/usr/bin/bash /home/error/.rvm/wrappers/%i/thin start -a $THIN_BIND -p $THIN_PORT
WorkingDirectory=/srv/www/%i
PrivateTmp=true

[Install]
WantedBy=multi-user.target

Ketika saya reboot, itu tidak berjalan:

$ systemctl --user status thin@redmine -l
● thin@redmine.service - A fast and very simple Ruby web server
   Loaded: loaded (/home/error/.config/systemd/user/thin@.service; enabled; vendor preset: enabled)
   Active: inactive (dead)

# systemctl status user@1000 -l
● user@1000.service - User Manager for UID 1000
   Loaded: loaded (/usr/lib/systemd/system/user@.service; static; vendor preset: disabled)
   Active: active (running) since Wed 2015-12-23 19:43:27 GMT; 13s ago
 Main PID: 613 (systemd)
   Status: "Startup finished in 38ms."
   CGroup: /user.slice/user-1000.slice/user@1000.service
           ├─613 /usr/lib/systemd/systemd --user
           └─615 (sd-pam)                                                          

Dec 23 19:43:27 redmine systemd[613]: Reached target Sockets.
Dec 23 19:43:27 redmine systemd[613]: Starting Sockets.
Dec 23 19:43:27 redmine systemd[613]: Reached target Timers.
Dec 23 19:43:27 redmine systemd[613]: Starting Timers.
Dec 23 19:43:27 redmine systemd[613]: Reached target Basic System.
Dec 23 19:43:27 redmine systemd[613]: Starting Basic System.
Dec 23 19:43:27 redmine systemd[613]: Reached target Default.
Dec 23 19:43:27 redmine systemd[613]: Startup finished in 38ms.
Dec 23 19:43:27 redmine systemd[613]: Starting Default.
Dec 23 19:43:27 redmine systemd[1]: Started User Manager for UID 1000.

Saya bisa memulainya secara manual, dan berfungsi:

$ systemctl --user start thin@redmine
$ systemctl --user status thin@redmine -l
● thin@redmine.service - A fast and very simple Ruby web server
   Loaded: loaded (/home/error/.config/systemd/user/thin@.service; enabled; vendor preset: enabled)
   Active: active (running) since Wed 2015-12-23 19:43:50 GMT; 5s ago
 Main PID: 1265 (ruby)
   CGroup: /user.slice/user-1000.slice/user@1000.service/thin.slice/thin@redmine.service
           └─1265 ruby /home/error/.rvm/gems/ruby-2.2.1@redmine/bin/thin start -a ::1 -p 8008

Dec 23 19:43:50 redmine systemd[613]: Started A fast and very simple Ruby web server.
Dec 23 19:43:50 redmine systemd[613]: Starting A fast and very simple Ruby web server...
Dec 23 19:43:52 redmine bash[1265]: /home/error/.rvm/gems/ruby-2.2.1@redmine/gems/htmlentities-4.3.1/lib/htmlentities/mappings/expanded.rb:465: warning: duplicated key at line 466 ignored: "inodot"

# systemctl status user@1000 -l
● user@1000.service - User Manager for UID 1000
   Loaded: loaded (/usr/lib/systemd/system/user@.service; static; vendor preset: disabled)
   Active: active (running) since Wed 2015-12-23 19:43:27 GMT; 40s ago
 Main PID: 613 (systemd)
   Status: "Startup finished in 38ms."
   CGroup: /user.slice/user-1000.slice/user@1000.service
           ├─613 /usr/lib/systemd/systemd --user
           ├─615 (sd-pam)                                                       
           └─thin.slice
             └─thin@redmine.service
               └─1265 ruby /home/error/.rvm/gems/ruby-2.2.1@redmine/bin/thin start -a ::1 -p 8008                                                               

Dec 23 19:43:27 redmine systemd[613]: Startup finished in 38ms.
Dec 23 19:43:27 redmine systemd[613]: Starting Default.
Dec 23 19:43:27 redmine systemd[1]: Started User Manager for UID 1000.
Dec 23 19:43:50 redmine systemd[613]: Created slice -.slice.
Dec 23 19:43:50 redmine systemd[613]: Starting -.slice.
Dec 23 19:43:50 redmine systemd[613]: Created slice thin.slice.
Dec 23 19:43:50 redmine systemd[613]: Starting thin.slice.
Dec 23 19:43:50 redmine systemd[613]: Started A fast and very simple Ruby web server.
Dec 23 19:43:50 redmine systemd[613]: Starting A fast and very simple Ruby web server...
Dec 23 19:43:52 redmine bash[1265]: /home/error/.rvm/gems/ruby-2.2.1@redmine/gems/htmlentities-4.3.1/lib/htmlentities/mappings/expanded.rb:465: warning: duplicated key at line 466 ignored: "inodot"

Bagaimana saya mencari tahu mengapa layanan ini tidak dimulai saat boot, dan membuatnya melakukannya?

Sistem operasinya adalah Fedora 23 x86_64, systemd 222-10.

Angka-angka yang akan saya pecahkan sendiri.

Petunjuk ada di sini, di output layanan pengguna:

Dec 23 19:43:27 redmine systemd[613]: Reached target Default.

Unit saya meminta untuk dimuat multi-user.target, tetapi tidak ada target seperti itu di sistem pengguna.

Saya mengubahnya ke default.targetdalam file unit, dinonaktifkan dan diaktifkan kembali layanan, dan sekarang mulai saat boot.

[Install]
WantedBy=default.target

lalu

$ systemctl --user disable thin@redmine
Removed symlink /home/error/.config/systemd/user/multi-user.target.wants/thin@redmine.service.
$ systemctl --user daemon-reload
$ systemctl --user enable thin@redmine
Created symlink from /home/error/.config/systemd/user/default.target.wants/thin@redmine.service to /home/error/.config/systemd/user/thin@.service.