VNC connection timeout when monitor is detached

I’ve set up many Linux systems that allow VNC without needing the monitor to remain attached once it’s built (i.e. headless). I’ve just set up a Rocky Linux 9 system with RealVNC and gotten that to work with the monitor attached. However, if I pull the monitor off, the VNC client fails to connect with a timeout error. I’ve tried 1) just pulling the HDMI connection, and 2) shutting the system down before detaching the monitor.

For the second method (the shutdown and detach) I see vncserver virtuald, x11-serviced, and x11-core services running once I’ve restarted the server. But the vnc client times out trying to connect.

Any thoughts? I really don’t want to have a monitor attached to this server, I’m using it as a VM host.

The solution was to rebuild the system and use tigervnc instead of realvnc.