How to Install and Setup Xen on Centos

Xen is a free open source software virtual machine monitor for Intel / PowerPC architectures. It is software that runs on a host operating system and allows several guest operating systems to be run on top of the host on the same computer hardware at the same time (just like VMWare software). Luckily Installing and managing XEN is quite easy under CentOS 5

Login as the root and type the following commands:

# yum install xen virt-manager kernel-xen

# chkconfig xend on

# reboot

Make sure you boot CentOS server using XEN kernel.

How do I install NetBSD / any Linux distro / Windows 2000 inside XEN?

Simply use gui tool called virt-manager:

# virt-manager &

Now just follow on screen instructions to setup new guest operating systems (VPS oses). virt-manager is Xen Management Consoles software. It can perform the common tasks of administering a Xen host such as configuring, starting, monitoring and stopping of Xen guests OS.

Installing CentOS 5.3 guest using the Internet

virt-install is a command line tool for provisioning new virtual machines using the "libvirt" hypervisor management library. Type the following command to install CentOS v5.3 64 bit as guest operating system in /vm:

# mkdir /vm

If you are using SELinux, enter:

# semanage fcontext -a -t xen_image_t "/vm(/.*)?"

# restorecon -R /vm

# ls -dZ /vm

Above will provide security context of Xen images. Finally, install CentOS 5.3 using the Internet mirror:

# virt-install \

--paravirt \

--name webserver01 \

--ram 512 \

--file /vm/webserver.nixcraft.com.img \

--file-size 10 \

--nographics \

--location http://mirrors.kernel.org/centos/5.3/os/x86_64/

Above will install CentOS as a paravirtualized Xen guest, with 512 MB of RAM, a 10 GB of disk, and from a web server, in text-only mode. You need to just follow on screen instructions.

Once installed you can use xm command to list, start, stop and manage xen vps:

# xen list

Attach console to domain / guest called webserver01:

# xm console webserver01

See xm command cheat sheet.

Installing CentOS 5.3 guest using DVD

Install a CentOS guest, using LVM partition, virtual networking, booting from the host CDROM, using VNC server/viewer (insert DVD into drive):

# virt-install \

--connect qemu:///system \

--name mailserver

--ram 500 \

--file /dev/HostVG/mailserver.cyberciti.biz \

--network network:default \

--accelerate \

--vnc \

--cdrom /dev/cdrom

Note you need qemu and virt-viewer installed on the host system.

Installing Fedora guest using DVD iso image stored on hard disk

Install a Fedora Linux, with a real partition (/dev/sdc), using a local DVD ISO image:

# virt-install \

--name www2 \

--ram 1000 \

--file /dev/sdc \

--network bridge:eth1 \

--cdrom /tmp/fedorabootdvd.iso