Fixing Unwanted Linux System Suspend Caused by gdm / lightdm

After upgrading to a newer Ubuntu, I found myself facing automatic system suspend events (look at /var/log/syslog) every 20 or 30 minutes. Here is how to fix them:

sudo -H -u lightdm dbus-launch --exit-with-session dbus-launch gsettings set com.canonical.unity-greeter idle-timeout 0

sudo -H -u lightdm dbus-launch --exit-with-session dbus-launch gsettings set org.gnome.settings-daemon.plugins.power lid-close-ac-action nothing

sudo -H -u lightdm dbus-launch --exit-with-session dbus-launch gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 0

sudo -H -u lightdm dbus-launch --exit-with-session dbus-launch gsettings set org.gnome.settings-daemon.plugins.power time-low 0

You might want to look at the power settings first which can be shown by:

sudo -H -u lightdm dbus-launch --exit-with-session gsettings list-recursively org.gnome.settings-daemon.plugins.power

If needed, login to the lightdm user by:

su lightdm -s /bin/bash