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Resolved pam_systemd(ftpd:session): Failed to connect to system bus

TimReeves

Regular Pleskian
Plesk Onyx, 17.0.17, Debian Jessie, vServer at Hetzner (KVM virtualisation)

On this new server, although FTP works fine, I am seeing quite frequently in /var/log/auth.log:

Nov 21 09:14:04 mail proftpd: pam_systemd(ftpd:session): Failed to connect to system bus: Permission denied
Nov 21 09:52:35 mail proftpd: pam_systemd(ftpd:session): Failed to connect to system bus: No such file or directory


I do not have this sort of error message on older servers runnung Ubuntu 14.04 and Plesk 12.5.

Any ideas why / how to stop it?

Cheers, Tim
 
Hi TimReeves,

you could try:

Code:
sudo update-rc.d dbus defaults
sudo service dbus restart
/etc/init.d/xinetd stop
/etc/init.d/xinetd start
 
Hi @UFHH01,

magic - that worked! I had not previously stumbled on D-Bus - a simple interprocess messaging system, used for sending messages between applications.

Being as I'm on Debian with systemd, it would be more futuristic using systemctl:

# update-rc.d dbus defaults
# systemctl restart dbus.service
# systemctl restart xinetd.service

Main thing - it works! Herzlichen Dank nach Hamburg.
 
Hi, having the same issue:

Code:
Jul 25 15:45:22 hostname proftpd[2961]: 0.0.0.0 (x.x.x.x[x.x.x.x]) - USER ftpuser: Login successful.

Jul 25 15:45:22 hostname proftpd: pam_unix(proftpd:session): session closed for user ftpuser

Jul 25 15:45:22 hostname proftpd: pam_systemd(proftpd:session): Failed to connect to system bus: Permission denied

Jul 25 15:45:22 hostname proftpd: pam_systemd(proftpd:session): Failed to connect to system bus: Permission denied

Jul 25 15:45:22 hostname systemd-logind[393]: Removed session 4002326.

tried:

Code:
sudo update-rc.d dbus defaults
sudo service dbus restart
/etc/init.d/xinetd stop
/etc/init.d/xinetd start

with dbus restart i got failure:
Code:
Failed to restart dbus.service: Operation refused, unit dbus.service may be requested by dependency only.
See system logs and 'systemctl status dbus.service' for details.

i learned it's coming from:

/lib/systemd/system/dbus.service

Code:
[Unit]
Description=D-Bus System Message Bus
Documentation=man:dbus-daemon(1)
Requires=dbus.socket
# we don't properly stop D-Bus (see ExecStop=), thus disallow restart
RefuseManualStart=yes

[Service]
ExecStart=/usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
ExecReload=/usr/bin/dbus-send --print-reply --system --type=method_call --dest=org.freedesktop.DBus / org.freedesktop.DBus.ReloadConfig
ExecStop=/bin/true
KillMode=none
OOMScoreAdjust=-900

That's why i tried a server restart without success, still same failure
 
i'm still struggling getting the point.

Looking into the syslog i do find following corresponding entry:

Code:
Jul 25 15:45:22 hostname proftpd[2961]: 0.0.0.0 (x.x.x.x[x.x.x.x]) - FTP session closed.
Jul 25 15:45:22 hostname systemd[2961]: Stopped target Default.
Jul 25 15:45:22 hostname systemd[2961]: Reached target Shutdown.
Jul 25 15:45:22 hostname systemd[2961]: Starting Exit the Session...
Jul 25 15:45:22  hostname systemd[2961]: Stopped target Basic System.
Jul 25 15:45:22  hostname systemd[2961]: Stopped target Paths.
Jul 25 15:45:22  hostname systemd[2961]: Stopped target Sockets.
Jul 25 15:45:22  hostname systemd[2961]: Stopped target Timers.
Jul 25 15:45:22  hostname systemd[2961]: Received SIGRTMIN+24 from PID 2961 (kill).
Jul 25 15:45:22  hostname systemd[1535]: Failed to get udev device from devnum 182:529297: No such device
Jul 25 15:45:22  hostname systemd[26685]: Failed to get udev device from devnum 182:529297: No such device
 
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