Edit Firewall Settings to Enable XDMCP Access
Problem: Could not make XDMCP connection to whitebox
Cause: The built-in firewall blocks XDMCP traffic
Fix: Open XDMCP related ports
1. SSH to whitebox, su
2. Do
/usr/sbin/lokkit
Select "Customize", in "Other Ports" field, append
xdmcp:udp x11:tcp
3. Save settings
4. Try again with X-Win32 connection, SUCCESS