faq-remote-X11-beta

Remote X11 (beta) - x2go and xpra

In general x2go is easier to use and sufficient for most scenarios. Xpra has better performance and uses less resources. Both clients connect through ssh and are generally faster than ssh -Y. Support for these is beta, x2go is more familiar to the support staff. Most linux systems do not have these tools installed, so you may need to request them.

We recommend using x2go. x2go is more familiar to the support staff and it is easier to use.

x2go

download

x2go can be downloaded from this page.

https://wiki.x2go.org/doku.php/download:start

Additional Steps

You will need to open System Preferences - Security - General - Temporarily 'Allow from anywhere' open the application, make sure you can reopen it. Then change your security setting back to 'App Store and Identified Developers'

For all systems off of the sbgrid network it will be easiest if you use the cmcd-vpn.

x2go requires XQuartz - see faq-using-sbgrid-programs if you do not already have it installed.

From the x2go application - Create a new session Make sure you fill out the following -

1. host - the host that you want to connect to.
2. login - your username
3. port - 22
4. Session type - Mate

You can adjust the resolution after the session has started.

Xpra

xpra has been described as 'tmux for X11'. It uses x264 encoding.

OSX to Linux workstation usage

For Mac OSX newer than 10.9 the installer is on their downloads page https://www.xpra.org/trac/wiki/Download

GUI version - https://xpra.org/dists/osx/x86_64/Xpra.pkg

For command line usage please us the 'pkg' installer located here - https://xpra.org/dists/osx/x86_64/Xpra.pkg

xpra gui

On remote system - copy xpra-launch.sh to your home folder and ./xpra-launch.sh or useone of the lines below.

Full desktop

tmux new-session -d -s "xpra-desktop" "xpra start-desktop –start=mate-session :$((10 + RANDOM % 999)) –pulseaudio=no –daemon=no"

Minimal termial window

tmux new-session -d -s "xpra-terminal" "xpra start –start=mate-terminal :$((10 + RANDOM % 999)) –pulseaudio=no –daemon=no"

open xpra gui

Select mode ssh - enter username, host and password info. If there is only one xpra session it will automatically connect to it. You can also save that info to a config file and launch that after.

To end the session on the remote system either tmux a and Ctrl-c or 'xpra stop'

xpra cli - keep it simple.

On your local Mac OSX system open a terminal window and run xpra start ssh/oconnor@sch-boltzmann/42 --start-child=xterm

With this one command you should have a remote xterm window come up. From there you can launch whatever application you need to run on the other system, including applications that need GLX extensions such as coot.

To disconnect, just ^c from the original terminal window(not the xterm that you connected to), or if you connect from another system it will automatically detach.

reattach to attach -

xpra attach ssh/oconnor@sch-boltzmann/42

Note the number 42. You need to pick a number that someone else on the system is not using. Do not use a low number that could be inuse by the system like 0 - 5, instead pick a higher number up to 999.

Note, if you simply close all the windows, including xterm, the remote server is still running ssh oconnor@sch-boltzmann xpra list Found the following xpra sessions: /run/user/46627/xpra: LIVE session at :666 xpra stop :666 xpra at :666 has exited.

Or if you wantesd the session to end when you opened the window - xpra start ssh/oconnor@sch-boltzmann/42 --start-child=xterm --window-close=shutdown

For all systems off of the sbgrid network it will be easiest if you use the cmcd-vpn.

Troubleshooting tips.

Ideally you would have already set up SSH Without a Password

Make sure you can ssh to the host without error. You should not need to type 'yes' for ssh keys, etc.

Press enter one time - is it waiting for password input?

connect to the remote host and type - xpra list

If there is an active session you can connect to it via `xpra attach ssh/user@host/42' from your client.

There could be an active session with no windows open. Stop the session and start again. 'xpra stop :42`

Try to launch a session from the host in a tmux or screen session on the remote server - ssh user@myhost" tmux xpra start :617 –daemon=no –start-child=xterm You should see a line that that contains xpra is ready. Detach with CTRL-b - d keys and then you can attach from your own system xpra attach ssh/oconnor@sch-boltzmann/617`

See Also `man xpra'