X11 forwarding not working (using Putty to connect to a CentOS 8 VM). What can be wrong?

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  and usually I need to restart the kernel entirely, losing all variables. This is a major hurdle in my workflow. I have tried running the pyplot command plt.switch_backend("Agg") to stop using X11 before disconnecting, but it does not help.

  Question

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• Configuring X Server of Windows 10 for WSL 2

  I know this issue is documented heavily and there are intricate details that are easy to miss. I tried a lot of ways by reading articles to get this working for almost a complete day.

  I will describe my problem briefly:

  I have installed Ubuntu 18.04 (WSL 2) on my Windows 10 (Version 1909 - OS Build 18363.1316). I am trying to open gvim files from Ubuntu in windows 10 using X server/client setup. The X Server on Windows 10 crashes 15-20 minutes after starting it.

  The steps I have followed for setup of X Server/Client are:

  1. Configured the X Client on Ubuntu by

     a. setting DISPLAY variable to IP address from /etc/resolv.conf with 0.0 attached at the end (WSL2)

     b. setting LIBGL_ALWAYS_INDIRECT variable to 1

  2. Installed ssh and xdm packages on Ubuntu and starting them up on opening the terminal using

     a. sudo service ssh start

     b. sudo service xdm start

     c. After starting both Xserver and Xclient, I checked the connectivity on TCP port 6000 with the following command

      nc -v <IP Address from Step 1.a> 6000
     

  3. On the X server setup on Windows 10

     a. I downloaded Xming and installed it

     b. I enabled Xming application in Windows Firewall on Public, Private and domain networks

     c. I configured XLaunch to run the following command (setting the flag "disable access control")

     Xming :0 -multiwindow -clipboard -ac 
     

     I can open my gvim files in windows but the issue is the server automatically closes after a few minutes (say 15-20 minutes). I looked at the log file of the Xming server. It shows something below:

  winInitMultiWindowWM - Could not open display, try: 5, sleeping: 5

  winInitMultiWindowWM - Failed opening the display. Exiting.

  winMultiWindowXMsgProc - Failed opening the display. Exiting.

  winProcEstablishConnection - Hello

  winInitClipboard ()

  winProcEstablishConnection - winInitClipboard returned.

  winClipboardProc - Hello

  DetectUnicodeSupport - Windows Vista

  winClipboardProc - DISPLAY=127.0.0.1:0.0

  winClipboardProc - Could not open display, try: 1, sleeping: 4

  winClipboardProc - Could not open display, try: 2, sleeping: 4

  winClipboardProc - Could not open display, try: 3, sleeping: 4

  winClipboardProc - Could not open display, try: 4, sleeping: 4

  winClipboardProc - Could not open display, try: 5, sleeping: 4

  Few Key points to note:

  1. I observe that sleeping value reduces after every iteration of trying and the server gets killed when the sleeping = 1

  2. I first open the Ubuntu and start the services ssh, xdm. Then, I open XLaunch and configure it to start the Xming server. I have tried the vice-versa as well

  3. I also tried installing and running VcxSrv with the right config settings and I am facing the same issue. I can post the log file of VcxSrv application

  Please help me to figure this out.

  Thanks,

  Bharadwaj