Problems with gdm but not with lightdm

  • Hi,
    In the same room :

    • 13 PC Debian Buster with GDM (Gnome Display Manager)
    • 8 old PC with Debian Buster with LightDM
      The master is one of the 13
      The master can see the 8 ones but none of the 12.
      Could it be related with the display manager ?
      (I've installed manually the latest version 4.5.6-0 : the oldest 4.1 used to be OK until some months (may be after an update of the Debian distribution)

    Vincent Le Mieux