RealVnc server does not show proper resolution after boot without monitor, Ubuntu 16.04

RealVnc server does not show proper resolution after boot without monitor.
vncserver -geometry 2560x1440   not working..!! Ubuntu 16.04 xserver is probably not compatible to
work with vncserver command. so there is one solution I came with,

solution:
add dummy display into /usr/share/X11/

use gtf command to generator proper resolution.
ex) gtf 2560 1440 60

/usr/share/X11/xorg.conf.d/xorg.conf/xorg.conf
====================================================
section "Device"
    Identifier  "Configured Video Device"
    Driver      "dummy"
    VideoRam 256000
#    VideoRam 2000000
EndSection

Section "Monitor"
    Identifier  "Configured Monitor"
    HorizSync 5.0 - 1000.0
    VertRefresh 5.0 - 200.0

# 2560x1440 @ 60.00 Hz (GTF) hsync: 89.40 kHz; pclk: 311.83 MHz
    Modeline "2560x1440_60.00"  311.83  2560 2744 3024 3488  1440 1441 1444 1490  -HSync +Vsync

EndSection

Section "Screen"
    Identifier  "Default Screen"
    Monitor     "Configured Monitor"
    Device      "Configured Video Device"
    DefaultDepth 24
    SubSection "Display"
    Depth 24
      Virtual 2560 1440
    EndSubSection
EndSection
====================================================

restart x display manager
sudo systemctl restart display-manager

check xserver log
sudo grep Modeline /var/log/Xorg.0.log


** Issue:
1. since it is placed in xorg.conf, it only work for dummy display for remote access,
 it won't work for physical monitor.  even rename it as 10-dummy.conf  it won't work with real monitor.   

RealVNC Connect on Ubuntu 16.04.4

https://boringtechtutorials.wordpress.com/2018/06/15/realvnc-connect-on-ubuntu-16-04-4/


To install RealVNC Connect run this terminal command.

$ sudo dpkg –i package name.deb

Once you install RealVNC Connect you need launch the setup wizard to login with your home subscription account.
In terminal run vnclicensewiz

$ vnclicensewiz

This will launch the wizard and you just need to login with your realvnc credentials. You will also need root password when requested.
To start RealVNC Connect service, run the following terminal command.

$ sudo systemctl start vncserver-x11-serviced.service

You will now see the RealVNC Connect icon on the Unity top bar.
You should now be able to connect to this system using RealVNC Viewer from another computer.
If you restart the computer RealVNC Connect will not atomically start. To make it start each time run the following command.

$ sudo systemctl enable vncserver-x11-serviced.service

This should complete the setup.