So after some research I found the existence of drop-ins for systemd service units.I'm trying to get the transmission-daemon package running as the pi user since it's the only way to get correct permission in the folder it downloads to. By default it runs as debian-transmission. I want to steer away from init.d and choose a systemd approach.Described in the systemd file (/lib/system/systemd/transmission-daemon.service):[Unit]Description=Transmission BitTorrent DaemonAfter=network.target[Service]User=debian-transmissionType=notifyExecStart=/usr/bin/transmission-daemon -f --log-errorExecReload=/bin/kill -s HUP $MAINPID[Install]WantedBy=multi-user.targetWith my drop-in replacement in /etc/systemd/system/transmission-daemon.service.d/local.conf:[Service]User=User=piGroup=piI ran sudo systemctl daemon-reload and sudo systemctl restart transmission-daemon. The drop-in is listed in sudo systemctl status transmission-daemon and shows as active nevertheless the daemon isn't running correctly and RPC connection doesn't work in a browser.Thanks in advance if you help, because I'm fumbled.
Changing systemd user with drop-in replacement for transmission-daemon not working
debian;systemd;raspberry pi;raspbian;transmission
Find the answer myself:Systemd is not the problem since it runs the service correctly but when transmission-daemon runs as the pi user it reads the config from $HOME/.config/transmission-daemon/settings.json owned by pi:pi, instead of /etc/transmission-daemon/settings.json owned by debian-transmission:debian-transmission.As a solution you can switch to using the config file in $HOME/transmission-daemon or pass -g /etc/transmission-daemon/settings.json in an ExecStart directive in the drop-in.