2023/06 - Testing RealVNC on RL8 by A.Denault.

After installation, we tested the VNC servers and Rocky8. 
We found the Xvnc-core did not work well for use due to high CPU usage, and broken redraws
in the vncviewer. These are the notes on testing after installation.

Quick note on how to get going

Setup your ~/.vnc/xstartup file (what desktop to start).
Then you can use the vncserver-virtual command to start and stop the desktops.

Xvnc-core - testing virtual desktop with  Vnc-core  (RealVNC X Server).

vncpasswd to set password. VNCAuth works using Xvnc server.

Configuration file is .vnc/config.d/Xvnc, I added
 AlwaysShared=1
 Authentication=VncAuth    # also can use SystemAuth for user passwords.

How to start/kill displays:

   vncserver-virtual :1
   vncserver-virtual  -geometry 1875x1100 :1   # geometry on work with Xvnc server
   vncserver-virtual -kill :1

Found the performance to be unusabled. RealVNC documenatation confirmed this and suggested 
using the Xorg Server for RHEL8 and later distributions.


Xorg server  Testing the System Xorg virtual desktop

To switch to/from Xorg server:
  vncinitconfig -disable-system-xorg      # SystemXorg=0 or uses Xvnc server (RealVNC provided)
  vncinitconfig -enable-system-xorg       # SystemXorg=1 or uses Xorg server. (xorg-x11-drv-dummy).
The command just set SystemXorg in this configuration file: .vnc/vncserver-virtual  

same commands to start/stop:
   vncserver-virtual :1
   vncserver-virtual -kill :1

Configuration file is .vnc/config.d/vncservre-x11-virtual 

Note: 
   --geometry is not supported in this mode. Setting Resolution is done in Desktop System Preferences.
   Only SystemAuth works (VNCAuth is not supported). 

~/.vnc/config.d/common configuration file.

Using this configuration file to test options on a per user based.
Common applies to Service Mode, User Mode, Virtual_Mode+SystemXorg, Virtal_Mode+Xvnc, etc).
Could be moved to /etc/vnc/policy.d/common so they can't be overridden by the users.

Conclusion  

IRTF decided to used RealVNC with Virtual_Mode+SystemXorg and XFCE as its VNC platform
to replace the CentOS6 vncserver. Since only SystemAuth is supported, we will setup
local accounts for VNC desktop, and VNC password changes will apply to these local account.

See user_setup.html for more informaiton on how the new stefan's VNCs were set up.