Ubuntu – Black screen after i close the lid and reopen

You need to configure logind.conf - this should not disable suspend, it should just to tell it to ignore the lid switch.

This will also override any of your user's power settings, and will work whether you are logged in or not (system-wide). You can configure it via running:

sudo nano /etc/systemd/logind.conf

You should like something like this:

Change HandleLidSwitch= line to this (with no # at the beginning - a # at the beginning of the line means it is a comment and will be ignored and the defaults will be used):

HandleLidSwitch=ignore

Here is a quote from a manual page - note it can take other values like lock, poweroff etc.

HandlePowerKey=, HandleSuspendKey=, HandleHibernateKey=, HandleLidSwitch=

Controls whether logind shall handle the system power and sleep keys and the lid switch to trigger actions such as system power-off or suspend. Can be one of "ignore", "poweroff", "reboot", "halt", "kexec", "suspend", "hibernate", "hybrid-sleep" and "lock". If "ignore", logind will never handle these keys. If "lock", all running sessions will be screen-locked; otherwise, the specified action will be taken in the respective event. Only input devices with the "power-switch" udev tag will be watched for key/lid switch events. HandlePowerKey= defaults to "poweroff". HandleSuspendKey= and HandleLidSwitch= defaults to "suspend". HandleHibernateKey= defaults to "hibernate".

The manual page for logind is here

Not a solution, but you may use this script as a workaround:

#!/bin/bash
qdbus com.canonical.Unity /com/canonical/Unity/Session com.canonical.Unity.Session.Lock &&
qdbus com.canonical.Unity  /com/canonical/Unity/Session com.canonical.Unity.Session.Suspend

This works with stock Ubuntu with Unity desktop. The approach is specific to Unity, although there are dbus calls to suspend regardless of the desktop environment. For 16.04 , one could use systemctl suspend command. See the relevant post: https://askubuntu.com/a/1795/295286

Alternative (older answer, edited)

One of the other tools for suspending, that works regardless of the Ubuntu version is pm-suspend. Problem is that it requires root privilege. To work around that, add pm-suspend to /etc/sudoers file to be executed without password ( more info here ).

In particular, in my /etc/sudoers I have the following:

# Allow using pm-suspend for my user without password
serg ALL = NOPASSWD: /usr/sbin/pm-suspend

Thus, you can use:

sh -c 'gnome-screensaver-command -l && sudo pm-suspend'

The sudo pm-suspend won't prompt you for password then.