Tutorial How to fix GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed

[DevOps]

On centos 7, there are instances where you get the error Unable to register authentication agent: GDBus.Errorrg.freedesktop.PolicyKit1.Error.Failed: Cannot determine user of subject
Error registering authentication agent: GDBus.Errorrg.freedesktop.PolicyKit1.Error.Failed: Cannot determine user of subject (polkit-error-quark, 0)

This usually happens when trying to restart a systemd service.

The workaround is as follows:

groupadd -g 23 nohidproc
usermod -a -G nohidproc polkitd
mount -o remount,rw,hidepid=2,gid=nohidproc /proc
systemctl restart polkit

Add the following in /etc/fstab as well

echo "proc /proc proc defaults,hidepid=2,gid=nohidproc 0 0" >> /etc/fstab

After mount the new mountpoint

mount -a

systemctl restart polkit