Today Ubuntu Server 14.04 was released and I downloaded the ISO to work with the latest from Canonical. I've used Citrix XenSever for several years on servers that I manage, but I'm teaching myself how to work with OpenStack and other "cloud" and virtualization technologies. I have a free server so I'm starting with a Xen (Xen Project) install.
Installing Xen (Xen Project) Hypervisor
I installed Xen: apt-get install xen-hypervisor-4.4
Then I double-checked /boot/grub/grub.cfg to verify the label given to the boot option for Xen. It was still "Ubuntu GNU/Linux, with Xen hypervisor", so I changed the grub default to use Xen in /etc/default/grub:
GRUB_DEFAULT="Ubuntu GNU/Linux, with Xen hypervisor"
Saved that file and ran: update-grub
Got this warning:
Including Xen overrides from /etc/default/grub.d/xen.cfg
WARNING: GRUB_DEFAULT changed to boot into Xen by default!
Edit /etc/default/grub.d/xen.cfg to avoid this warning.
Nice! So I was ready to reboot into the Xen kernel:shutdown -r now
Once the server came back up, I ran xl list as root to check if Xen was ready to go.
Name ID Mem VCPUs State Time(s) Domain-0 0 16066 8 r----- 17.2
Dom0 was set up, so that was good!
Setting up the Networking
I needed to reconfigure networking so I could bridge Virtual Machines (VMs) with the physical network of the host. I edited /etc/network/interfaces to show:
auto lo
iface lo inet loopback
auto xenbr0
iface xenbr0 inet static
bridge-ports eth0
address 10.1.1.66
netmask 255.255.255.192
network 10.1.1.64
broadcast 10.1.1.127
gateway 10.1.1.65
dns-nameservers 8.8.4.4 8.8.8.8
# The primary network interface
#auto eth0
iface eth0 inet manual
Setting up VM Storage
Storage for the VMs can be setup to use a file, or a block device that will hold the entire file system. Using block devices allows for faster IO, so I used LVM instead of a disk image. (see http://wiki.xen.org/wiki/Storage_options)
I already had a LVM volume group set up from the initial server install, so vgdisplay gave me the name of the volume group, "Host-A-vg". (If I didn't already have a volume group, I would have had to use pvcreate and vgcreate to set it up.)