systemd : how do I know why a disabled service is running ?

[drknut]

just after boot :

Code: Select all

# systemctl status upower
● upower.service - Daemon for power management
   Loaded: loaded (/usr/lib/systemd/system/upower.service; disabled; vendor preset: enabled)
   Active: active (running) since Thu 2018-12-27 15:51:21 CET; 1h 9min ago
     Docs: man:upowerd(8)
 Main PID: 7846 (upowerd)
    Tasks: 3
   CGroup: /system.slice/upower.service
           └─7846 /usr/libexec/upowerd

Dec 27 15:51:21 host.domain.net systemd[1]: Starting Daemon for power management...
Dec 27 15:51:21 host.domain.net systemd[1]: Started Daemon for power management.

the "systemctl list-dependencies --reverse upower" command returns no interesting info.

I know that the "system mask upower" could solve this "problem", but I need first to understand why this service is started.