Changes

<table border="0" cellspacing="0" width="100%"><tr><td width="20%">[[Configuring a VNC based Graphical Console for a Xen Paravirtualized domainU Guest|Previous]]<td align="center">[[Xen Virtualization Essentials|Table of Contents]]<td width="20%" align="right">[[Adding Disk, CDROM and DVD Devices to a Running Xen domainU Guest System|Next]]</td><tr><td width="20%">Configuring a VNC based Graphical Console for a Xen Paravirtualized domainU Guest<td align="center"><td width="20%" align="right">Adding Disk, CDROM and DVD Devices to a Running Xen domainU Guest System</td></table><hr>  <htmlet>xen</htmlet>  In the previous chapter we looked at enabling VNC support in domain0 for the purpose of providing a remote graphical display for a Xen domainU guest. This approach works well in situations where only one graphical desktop is required. In situations where multiple graphical desktops are required (for example, it is quite likely that more than one user will want to be logged into a desktop at any one time) it is necessart necessary to run instances of the VNC server on the domainU guest rather than rely on the VNC support provided by domain0. The purpose of this chapter is to describe in detail how to achieve such a configuration.

The very first step in the configuration process involves ensuring that VNC support is installed on the domainU guest. As domainU systems often use a mininal minimal configuration it is possible that VNC has yet to be installed. the The precise steps to install VNC vary between distributions. Check the documentation for your chosen distribution if you are unsure. A few examples are:

The ''vncserver'' tool will prompt for a password which will be required each time a remote user attempts to connect to the desktop. At this prompt enter a suitable password to protect access to the desktop. Once a suitable password has been provided vncserver will start a new desktop in the background connected to port 5901 ready for a remote user to connect to using ''vncviewer''. The following transcript show shows the typical output from an initial launcd launch of a vncserver session:

To establish a secure connected connection we need to use SSH tunneling to establish an encrypted connection. This is achieved by first establishing the tunnel using the ''ssh'' command. In doing so we will map port 5901 on our local system to port 5901 on the remote domainU system (assuming that the VNC session is configured on display :1). This connection would be established as follows:

When the desktop appears you will notice that it doesn't look much like the standard desktop you would expect to see on most modern Linux distributions. In fact it may will look something like the following figure:

As long as the vncserver session is running the desktop will continue to run regardless of whether a ''vncviewer'' instance is connected. this This means that you can exit from ''vncviewer '' and reconnect later and find the your desktop exactly as you left it.

Before closing down the actual VNC server session it is important to verify that any applications running on the desktop in question have been cleanly exited to avoid loss of data. Once all applications are closed , log out of the desktop environment in the ''vncviewer'' session and then exit ''vncviewer''.