TigerVNC config with Ubuntu 20.04, black screen

I installed TightVNC on a Ubuntu20.04* machine in order to use it remotely from my macbook pro. I have followed this tutorial,

And it works with the fce4 desktop. However I have a black screen whenever I try to use the gnome desktop with it: I tried to change the config follwing this issue, but nothing seems to work.

Here is ~/.vnc/xstartup

#!/bin/sh
unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS
export XKL_XMODMAP_DISABLE=1
export XDG_CURRENT_DESKTOP="GNOME-Flashback:GNOME"
export XDG_MENU_PREFIX="gnome-flashback-"
[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &
gnome-session --builtin --session=gnome-flashback-metacity --disable-acceleration-check --debug &
nautilus &
gnome-terminal &

my /etc/systemd/system/vncserver@.service

[Unit]
Description=Start TightVNC server at startup
After=syslog.target network.target
[Service]
Type=forking
User=ben
Group=ben
WorkingDirectory=/home/ben
PIDFile=/home/ben/.vnc/%H:%i.pid
ExecStartPre=-/usr/bin/vncserver -kill :%i > /dev/null 2>&1
ExecStart=/usr/bin/vncserver -depth 24 -geometry 1280x800 -localhost :%i
ExecStop=/usr/bin/vncserver -kill :%i
[Install]
WantedBy=multi-user.target

And the service file /etc/systemd/system/vncserver@.service

[Unit]
Description=Start TightVNC server at startup
After=syslog.target network.target
[Service]
Type=forking
User=ben
Group=ben
WorkingDirectory=/home/ben
PIDFile=/home/ben/.vnc/%H:%i.pid
ExecStartPre=-/usr/bin/vncserver -kill :%i > /dev/null 2>&1
ExecStart=/usr/bin/vncserver -depth 24 -geometry 1280x800 -localhost :%i
ExecStop=/usr/bin/vncserver -kill :%i
[Install]
WantedBy=multi-user.target

The sudo systemctl status vncserver@1 command returns:

● - Start TightVNC server at startup Loaded: loaded (/etc/systemd/system/vncserver@.service; enabled; vendor preset: enabled) Active: inactive (dead) since Mon 2021-02-22 12:26:43 CET; 4min 53s ago Process: 11916 ExecStop=/usr/bin/vncserver -kill :1 (code=exited, status=0/SUCCESS) Main PID: 1235 (code=exited, status=0/SUCCESS)
Feb 22 12:01:51 ben-monster gnome-session-binary[1305]: WARNING: App 'org.gnome.Shell.desktop' exited with code 1
Feb 22 12:01:51 ben-monster gnome-session-b[1305]: unable to create file '/home/ben/.cache/dconf/user': Permission denied. dconf will not work properly.
Feb 22 12:01:51 ben-monster gnome-session[1305]: gnome-session-binary[1305]: CRITICAL: We failed, but the fail whale is dead. Sorry....
Feb 22 12:01:51 ben-monster gnome-session-binary[1305]: WARNING: App 'org.gnome.Shell.desktop' respawning too quickly
Feb 22 12:01:51 ben-monster gnome-session-binary[1305]: Unrecoverable failure in required component org.gnome.Shell.desktop
Feb 22 12:01:51 machine-name gnome-session-binary[1305]: CRITICAL: We failed, but the fail whale is dead. Sorry....
Feb 22 12:26:43 machine-name org.gtk.vfs.Daemon[1913]: A connection to the bus can't be made
Feb 22 12:26:43 machine-name vncserver[11916]: Killing Xtigervnc process ID 1235... which was already dead
Feb 22 12:26:43 machine-name vncserver[11916]: Cleaning stale pidfile '/home/ben/.vnc/machine-name:1.pid'!
Feb 22 12:26:43 machine-name systemd[1]: : Succeeded.

Furthermore, I Have the error message on my blackscreen:

Could not update ICEAuthority file /run/-/user//-ICEAuthority

It is probably a config or a rights error, but after two days of playing around, I am starting to lose faith.

2 Answers

I just followed your configuration with few changes and I think I got what your want in the end:

. My changes were:

I fixed the line:

ExecStartPre=-/usr/bin/vncserver -kill :%i > /dev/null 2>&1

by

ExecStartPre=/usr/bin/vncserver -kill :%i > /dev/null 2>&1

whitout the '-' character before /usr/bin

In addition to this, I changed the references to the name of the user from 'ben' to my user in:

User=ben
Group=ben
WorkingDirectory=/home/ben
PIDFile=/home/ben/.vnc/%H:%i.pid

Thus, my file ended up as:

User=my_user
Group=my_user
WorkingDirectory=/home/my_user
PIDFile=/home/my_user/.vnc/%H:%i.pid

Assuming that your user actually is ben, I think you have some files with limited permitions on /home/ben home folder. You can check this question for details about fix it. Maybe you need to give the ownership of files in this directory to the user ben using the command chown or just change the permition using chmod.

I got it with uncommenting "WaylandEnable=false" from /etc/gdm3/custom.conf

Then

sudo apt update
sudo apt install xserver-xorg-video-dummy
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.bak # this file may not exist so if there is an error, it can be ignored
sudo cp /etc/X11/vncserver-virtual-dummy.conf /etc/X11/xorg.conf

Note: Following these steps will result in any connected monitors displaying a blank screen. If you need to use a monitor, run sudo mv /etc/X11/xorg.conf /etc/X11/xorg.conf.dummy and reboot