Cannot use systemctl as a user after a "sudo su - media" : Failed to connect to bus: $DBUS_SESSION_BUS_ADDRESS and $XDG_RUNTIME_DIR not defined

SebMa

3/29/24, 3:47 PM

I'm trying to create a service as a user but it does not work :

admin $ sudo su - media
$ systemctl --user edit fmgr-copro.service --full --force
Failed to connect to bus: $DBUS_SESSION_BUS_ADDRESS and $XDG_RUNTIME_DIR not defined (consider using --machine=<user>@.host --user to connect to bus of other user)
$ exit
admin $ systemctl status dbus -n 2
● dbus.service - D-Bus System Message Bus
     Loaded: loaded (/lib/systemd/system/dbus.service; static)
     Active: active (running) since Wed 2023-03-22 15:07:24 CET; 1 week 0 days ago
TriggeredBy: ● dbus.socket
       Docs: man:dbus-daemon(1)
   Main PID: 869 (dbus-daemon)
      Tasks: 1 (limit: 38289)
     Memory: 1.7M
        CPU: 4.125s
     CGroup: /system.slice/dbus.service
             └─869 @dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation --syslog-only

Mar 28 10:09:57 myServer dbus-daemon[869]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' r>
Mar 28 10:09:57 myServer dbus-daemon[869]: [system] Successfully activated service 'org.freedesktop.hostname1'
admin $ sudo su - media
$ echo $XDG_RUNTIME_DIR

$ echo $DBUS_SESSION_BUS_ADDRESS

$

EDIT0 : It seems the DBUS_SESSION_BUS_ADDRESS and XDG_RUNTIME_DIR variabes are cleared after a sudo su - media.

Can you help me ?

458

1 + 1

sudo

dbus

services

systemd

22.04

SebMa

4/3/24, 8:55 AM

Found a solution [here](https://unix.stackexchange.com/a/245866/135038)

Score:0

Ubuntu

Erik Sjölund

4/30/24, 6:40 AM

Avoid using su. Instead use the tools that comes from systemd

machinectl
systemd-run

(The question is about interactive use but for completeness I also add noninteractive use)

Interactive use

sudo machinectl shell username@

Noninteractive use

sudo systemd-run \
              -M username@ \
              --user \
              --quiet \
              --collect \
              --pipe \
              --wait \
             mycommand

Reference

su is "not a tool for opening a completely new login session" according to the original author of systemd https://github.com/systemd/systemd/issues/7451#issuecomment-346787237

+ 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Cannot use systemctl as a user after a "sudo su - media" : Failed to connect to bus: $DBUS_SESSION_BUS_ADDRESS and $XDG_RUNTIME_DIR not defined

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