############################### __ __ ____ ___ \ \/ /___ _ __ |___ \ / _ \ \ // _ \ '_ \ __) || | | | / \ __/ | | | / __/ | |_| | /_/\_\___|_| |_| |_____(_)___/ ############################### University of Cambridge Computer Laboratory 3 November 2004 http://www.cl.cam.ac.uk/netos/xen/ What is Xen? ============ Xen is a Virtual Machine Monitor (VMM) originally developed by the Systems Research Group of the University of Cambridge Computer Laboratory, as part of the UK-EPSRC funded XenoServers project. Xen is freely-distributable Open Source software, released under the GNU GPL. The 2.0 release offers excellent performance, hardware support and enterprise-grade features such as live migration. Linux 2.6, 2.4 and NetBSD 2.0 are already available for Xen, with more operating system ports on the way. This file contains some quick-start instructions to install Xen on your system. For full documentation, see the Xen User Manual. If this is a pre-built release then you can find the manual at: dist/install/usr/share/doc/xen/pdf/user.pdf If you have a source release, then 'make -C docs' will build the manual at docs/pdf/user.pdf. Quick-Start Guide - Pre-Built Binary Release ============================================ [NB. Unless noted otherwise, all the following steps should be performed with root privileges.] 1. Install the binary distribution onto your filesystem: # sh ./install.sh Amongst other things, this will install Xen and XenLinux kernel files in /boot, kernel modules and Python packages in /lib, and various control tools in standard 'bin' directories. 2. Configure your bootloader to boot Xen and an initial Linux virtual machine. Note that Xen currently only works with GRUB: less common alternatives such as LILO are *not* supported. You can most likely find your GRUB menu file at /boot/grub/menu.lst: edit this file to include an entry like the following: # title Xen 2.0 / XenLinux 2.6 # kernel /boot/xen-2.0.gz dom0_mem= console=vga # module /boot/vmlinuz-2.6-xen0 root= ro console=tty0 For you should specify the amount of memory, in kilobytes, to allocate for use by your initial XenLinux virtual machine. Note that Xen itself reserves about 32MB memory for internal use, which is not available for allocation to virtual machines. For , specify your usual root partition (e.g., /dev/hda1). 3. Reboot your system and select the "Xen 2.0 / XenLinux 2.6" menu option. After booting Xen, XenLinux will start and your initialisation scripts should execute in the usual way. Quick-Start Guide - Source Release ================================== First, there are a number of prerequisites for building a Xen source release. Make sure you have all the following installed, either by visiting the project webpage or installing a pre-built package provided by your Linux distributor: * GCC (preferably v3.2.x or v3.3.x; older versions are unsupported) * GNU Make * GNU Binutils * Development install of libcurl (e.g., libcurl-dev) * Development install of zlib (e.g., zlib-dev) * Development install of Python v2.2 or later (e.g., python-dev) [NB. Unless noted otherwise, all the following steps should be performed with root privileges.] 1. Download and untar the source tarball file. This will be a file named xen-unstable-src.tgz, or xen-$version-src.tgz. You can also pull the current version from the SCMS that is being used (Bitkeeper, scheduled to change shortly). # tar xzf xen-unstable-src.tgz Assuming you are using the unstable tree, this will untar into xen-unstable. The rest of the instructions use the unstable tree as an example, substitute the version for unstable. 2. cd to xen-unstable (or whatever you sensibly rename it to). The Linux (2.4 and 2.6), netbsd and freebsd kernel source trees are in the $os-$version-xen-sparse directories. On Linux: 3. For the very first build, or if you want to destroy existing .configs and build trees, perform the following steps: # make world # make install This will create the directories linux-2.6.11-dom0/ and linux-2.6.11-domU/ after first cleaning everything. It will create and install into the dist/ directory which is the default install location. It will build the xen binary (xen.gz), the boot images for dom0 and an unpriviledged guest kernel (vmlinuz-2.6.11-xen0 and vmlinuz-2.6.11-xenU respectively), the tools and the documentation. 4. To rebuild an existing tree without modifying the config: # make dist This will build and install xen, kernels, tools, and docs into the local dist/ directory. 5. To rebuild a kernel with a modified config: # cd linux-2.6.11-xen0 # or linux-2.6.11-xenU # make ARCH=xen menuconfig # or xconfig # cd .. # make dist # make install You can copy your own config into linux-2.6.11-xen0 first. Alternatively, you can also copy your config file to dist/install/boot/config-$version-xen0/U. This is picked up when a make dist is done. Include the ARCH=xen directive for all make commands when building the kernels. 6. To see a full list of targets and a brief description, type: # make help 7. Edit your grub.conf file as described above to have an appropriate entry for your new kernel.