Xubuntu Remote Desktop with VNC4Server

A thread on ubuntuforms.org , called "HOWTO: Set up VNC server with resumable sessions", described how to do something that I have been trying to do with Xubuntu for a while. Ubuntu remote desktop access is easier due to the inclusion of the vino-server. The thread went on for a number of pages and this post attempts to capture all of the bits relevant to getting this working on Xubuntu. This was done on a Fiesty Fawn installation, but should work on Edgy.

The objective is

• to allow remote access to a Xubuntu desktop and,
  
• in this case, this will be in the form of a resumable session, and
• to not use any GNOME libraries.

1. Install the required applications:

sudo apt-get install vnc4server xinetd xvnc4viewer

2. If you do not already have it installed, install ssh, which should bring in the client and the server:

sudo apt-get install ssh

3. Open the "Login Window" applet in the Applications --> Settings menu. You should be prompted for your password to access this.
4. Choose the "Remote" tab and select one of the options from the Style dropdown. I select Plain.
5. At the bottom of the tab, there is a button called "Configure XDMCP...". Click and make sure that the "Honor indirect requests" is NOT selected.
6. Using your favourite text editor, open /etc/gdm/gdm.conf for editing. You will need superuser privileges, so it should be something like:

sudo vi /etc/gdm/gdm.conf
OR
sudo nano /etc/gdm/gdm.conf

EDIT: The preferred file to edit is gdm.conf-custom as changes made to this file will survive an upgrade of GDM. Of the changes below, you should only need to add the RemoteGreeter line under [daemon] and AllowRemoteRoot under [security]. The [xdmcp] items were already in place.

7. In this file, in the [daemon] section, uncomment (i.e. remove the leading '#' sign) from the line which starts "RemoteGreeter=/usr/lib/gdm/gdmlogin".
8. In the [security] section, I change the AllowRemoteRoot to false.
9. In the [xdmcp] section, make sure Enable=true and HonorIndirect=false.
10. Now, to create an entry for xinetd to start each time it receives a connect request, create a file called Xvnc in /etc/xinetd.d. In /etc/xinetd.d/Xvnc, put the following text:

service Xvnc
{
type = UNLISTED
disable = no
socket_type = stream
protocol = tcp
wait = yes
user = root
server = /usr/bin/Xvnc
server_args = -inetd :1 -query localhost -geometry 1024x768 -depth 16 -once -fp /usr/share/fonts/X11/misc -DisconnectClients=0 -NeverShared passwordFile=/root/.vncpasswd
port = 5901
}

EDIT: Important: The text starting at "server_args..." and ending at ".../root/.vncpassword" is all ONE line. If you cut-and-paste, it might paste it as multiple lines instead of one long line.

EDIT2: Add "-extension XFIXES" to the end of the "server_args" line to get past the End of Stream problem.

EDIT3: Also note that the default setting to allow multiple logins in GDM has changed. I had a follow up post about this, but anotherstuart pointed out that it was missing here. See comments. Thanks!

NOTE: The font path in the -fp argument is slightly different from what was in the original thread. If you search in launchpad.net, you'll find some bugs about this.

11. Create a password for xinetd, by running

sudo vncpasswd /root/.vncpasswd

12. Restart xinetd by running:

sudo /etc/init.d/xinetd stop
sudo killall Xvnc
sudo /etc/init.d/xinetd start

You may also need to reboot to get some of the other changes to take effect.

To test that it is working, either

1. Use

xvnc4viewer :1

to start a session on the machine, or

2. Connect from another machine using a client like tightvnc.

You should get a graphical login.

NOTE: The session created does not end if you terminate the connection. It persists until you actually log out. This is useful if you are on a connection that drops out or if you login to start a job and need to disconnect without killing the job.

Once this is working, you can also tunnel this over an ssh connection, depending on your required level of paranoia.

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