D&C GLug - Home Page

[ Date Index ] [ Thread Index ] [ <= Previous by date / thread ] [ Next by date / thread => ]

Re: [LUG] Commandeering X


On 22/01/14 14:24, Philip Hudson wrote:
> My LMDE host is multi-seat. Only one seat has an X display; all others are
> dumb character-mode terminals. Sitting at one of the dumb terminals (tty,
> sty, pty...), how can I cause the X display to dismiss the mdm greeter and
> start my desktop session, exactly as if I had walked over to the seat with
> the X display and used its keyboard to login?

Now I'm really confused: I thought it was pretty obvious that XDMCP was
what you needed but now I have no idea what it is you're trying to achieve.

Firstly, your LDME host is multi-seat in only the same way that any
other Linux machine is, surely? You don't actually have multiple
physical keyboard/mouse/monitors attached to a single machine, you just
have an X display sitting at the MDM greeter on tty7 and all of the
usual alternative logins available, so you could CTRL+ALT+F1 on the box
and get a terminal prompt, or login via SSH, etc. Just like any other
Linux box.

Now, if you're sat at one of the dumb terminals (let's say it's on the
local machine and you've just done CTRL+ALT+F1, or you've just SSH'd
into it from another PC)  then there isn't going to be any X, let alone
a MDM greeter. You're going to be looking at something like:


In the first case, you could then start X by creating a .xinitrc file
and filling it with the correct information for your preferred desktop
session to begin, MDM being completely bypassed when you issue "startx".
On the SSH session, you can't start X, full stop. You could have SSH'd
in with the -X or -Y options and commenced X forwarding as Gordon
explained, but that apparently isn't what you want to do either.

What *exactly* is it that you want to do, because it's just not at all
clear. You don't seem to want a mirrored display (the sort of thing you
could achieve with VNC, RDP, LogMeIn, NXmachine, etc), SSH forwarding
isn't what you want either and you haven't commented on XDMCP, which I
thought was what you needed. If none of those are what you want, pretty
much the only thing left is to fall back on Xephyr/Xnest and run a
nested X environment on the target box hosted from the LDME machine. You
can do this fullscreen if required.

I use remote X, SSH forwarding, multiple concurrent X sessions and
VNC/RDP all the time so I'm really comfortable with this stuff - I know
I could tell you exactly what to do if I could just figure out what your
goal is and why XDMCP or SSH+X forwarding isn't suitable.

One of us is very confused, and it may well be me.


The Mailing List for the Devon & Cornwall LUG
FAQ: http://www.dcglug.org.uk/listfaq