What is Xen?
Xen is a free software virtual machine monitor for IA-32, x86-64, IA-64 and PowerPC 970 architectures. It allows several guest operating systems to be executed on the same computer hardware, at the same time.
A Xen system is structured with the Xen Hypervisor as the lowest and most privileged layer. Above this layer are one or more guest operating systems, which the hypervisor schedules across the physical CPUs.
The first guest operating system (also called as host operating system) domain 0 or dom0 in Xen terminology is booted when the hypervisor boots and gets special management privileges and direct access to the physical hardware. The system administrator logs in to dom0 to start other guest operating systems. In Xen terminology, other guest operating systems are referred to as domain U or domU.
Novell provides package updates for Xen Hypervisor and Xen enabled Linux kernels.
Check the following links for more information on Xen:
Installing Xen on SLES 10 through YaST
Do the following steps to install Xen on SLES 10.
- Open YaST and type vi in the filter text box .
- Double-click the Install Hypervisor and Tools to install Xen packages.
- Click Continue in the dialog box that appears.
- Click OK to complete the installation. Type Boot in the Filter text box.
- Select Xen from the Boot Loader menu.
- When you set Xen as default, the following screen appears.
- Reboot the system.
- Verify that system reboots with Xen kernel, by executing the command on terminal uname -r. Check that out put of this command will show the xen kernel version.
- Open YaST and type vir. Create Virtual Machines and Virtual Machine Manager applications appear on the YaST screen.
- Create Virtual Machines: Creates new virtual machines.
- Virtual Machine Manager: Manages new virtual machines. You can also create a virtual machine by using Virtual Machine Manager.
Creating a Virtual Machine (VM)
In the following steps assume that you are creating a virtual machine of SLES 10.
Do the following steps:
- Click the Create Virtual Machines application in YaST. It invokes a window for creating virtual machine.
- Click Forward. The subsequent screens are self descriptive and guide you to create a virtual machine.
Select the first option because you are installing operating system from scratch. Click Forward.
- Select the operating system that you are installing on the virtual machine. (Select SLES 10 as assumed above). Click Forward.
- Specify the machine settings required for virtual machine. You can change the default parameters by clicking on the setting. In addition, you can also change the default name of the virtual machine, hardware configuration, etc. Click OK to save your changes.
- Click the Hardware tab from the Screen*(Hyperlink). Change the memory setting, allocated processors of virtual machine. Click Apply for these changes to take effect immediately.
- Click the Operating System Installation tab from the Screen*(Hyperlink). Specify the installation source used for installing operating system. In this example, it is Network URL. Click Apply.
NOTE: You can also install from a virtual disk or an autoYaST file.
- Click OK to save your changes. And to start the installation of operating system. The Installation console appears.
The operating system installation is similar to the SLES 10 installation.
- After installing SLES 10 on the virtual machine, click the Virtual Machine Manager from the YaST.
The Virtual Machine Manager manages the virtual machines. You can start, stop, and delete the virtual machine by using this console. You can also monitor the resources used by the different virtual machines.
- Double-click a virtual machine and its console appears. The console has the name of the virtual machine. You can now use the virtual machine as a real machine. Use console to start and stop the virtual machine.
- Use the same procedure to create virtual machines of different guest operating systems.
Enjoy using virtualization on SLES 10.