Headless Ubuntu 20.04 change resolution w/o breaking nautilus-admin

Question

I’m running Ubuntu 20.04 desktop headless. Using NoMachine to connect to the headless desktop using dummy video driver (need desktop to use nautilus-admin). I am not able to set my preferred resolution 1920x1024 w/o breaking nautilus-admin. Xrandr shows highest/current resolution 1360×768.

I have tried:

1. DVI dongle, works for a time then the display is lost (but when it works works well!!)
2. using NoMachine virtual display driver, breaks nautilus-admin
3. xrandr adding mode for undetected resolution didn’t do anything (added new resolution using cvt then added mode to xrandr):

Screen 0: minimum 320×240, current 1360×768, maximum 1920×1080
default connected primary 1360x768+0+0 0mm x 0mm
   1360×768      60.00* 
  [removed other resolutions for brevity ]
   1920×1080_60.00  59.96

4. created xorg.conf to /usr/share/X11/xorg.conf.d/, added modeline 1920x1080 to xorg.conf, breaks nautilus-admin (is this a bug?!)

    Identifier  "Configured Video Device"
    Driver      "dummy"
==>Modeline    "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync
EndSection

Does anyone have any other suggestions, would using a dummy dongle for vga work differently/better? Thanks in advance.

Answer 1

I was able to finally get this to work by following these instructions https://ubuntuforums.org/showthread.php?t=2296872 I removed the xorg.conf file I had created in the original post and followed the instructions at the above link. I had to comment out the 1920X1080 modeline to get it to work (not sure why but it worked so I'm not complaining). Was able to connect to the desktop at the desired resolution 1920x1080 using NoMachine. The changes have survived two reboots and a shutdown. More importantly nautilus-admin is working. Not sure why this configuration works vs the original post but I'm happy in either case.