Comment 32 for bug 1712089

I have a variation of this: pardon any imprecision here I am NOT an expert sysadmin, I am a mid-stage learning Linux enthusiast.

I am running Lubuntu 16.04 on a home server and want to use VNC to vino to reach it remotely.

Vino works fine - tested local and remote, *when I have the desktop of the server PC open and logged in*.

What I want to do is leave vino NOT running, until I use an SSH session to start it.

When remoting in to do this, I DO get the MIT-MAGIC-COOKIE issue here, initially, until I issue

    export DISPLAY=:0

- which then solves that, and lets me run the /usr/lib/vino/vino-server command and allworks fine.

BUT::: that only works when the server PC has a local (idle) login active at it's desktop.

If I log OUT that local session, then any remote SSH attempt lets me in normally, but
attempting then to run vino, gives this error

"Failed to connect to Mir: Failed to connect to server socket: No such file or directory
Unable to init server: Could not connect: Connection refused "

-- REGARDLESS of using export DISPLAY=:0 on either (or both) client and server.

So the distinction is purely, is there a locally logged-in session, or not. How does that affect this, and is there a workaround ?

I have researched this, and advice such as 'xhost +' has been tried and does not work.

I've also been advised to use more complex forms of he export command such as

    export DISPLAY=1.0

and
    export DISPLAY-<locapipaddress>:1.0

- which also don't solve it.

One thing I think a lot of newbies and mid-rangers like me struggle to get a handle on, is how X windows really works and why these odd permssions-to-screens are managed.

More confusingly, the client I'm using is Lubuntu 18.04, which is Ubuntu but with LXDE in place of Gnome, and (I think) LXQt this time ? or is that not default ? Or is it Wayland ? forgive me but how are we non-experts to work out which of these esoteric screen drive structures is in use, with the choices so much in flux ?

I think some forums consider this 'worked around' - it's not for me, its a live issue and there's no fix I've found yet.

All constructive advice very much appreciated.

thanks
Mike
London