Bash script to install Ubuntu 12.04 as a Xen paravitualized domU guest on a Xen host with LVM.

ubuntu-domU.sh

#!/bin/bash
# Script to download, configure, and install Ubuntu as a Xen domU
# Uses existing LVM Volume Group.  Must be run as root/sudo.
# Based on instructions at https://help.ubuntu.com/community/Xen

# User Configurable Settings
NAME=ubuntu     # name of Domain to create
VG=/dev/domU    # existing volume group in which to create a logical volume
LV=$NAME        # name of the new logical volume to create
LV_SIZE=5G      # size of the new logical volume
MEM_SIZE=512    # memory to allocate to this VM
RELEASE=precise	# "precise" (12.04LTS) or "quantal" (12.10)

# Ubuntu distro settings.  Change mirror or version as required.
IMAGEDIR=/var/lib/xen/images/ubuntu-netboot
MIRROR=http://ubuntu.arcticnetwork.ca/
DISTRO=/ubuntu/dists/$RELEASE/main/installer-amd64/current/images/netboot/xen

#Create Disk
lvcreate -L $LV_SIZE -n $LV $VG

#Get Ubuntu Netboot kernel and ramdisk
if [ ! -d "$IMAGEDIR" ]; then
        mkdir -p $IMAGEDIR
        cd $IMAGEDIR
        wget $MIRROR/$DISTRO/initrd.gz
        wget $MIRROR/$DISTRO/vmlinuz
fi

#Create pre-install Xen Config
CONFIG=/etc/xen/$NAME.cfg
if [ -f "$CONFIG" ];
then
        mv $CONFIG $CONFIG.old
fi

# on_reboot="destroy" is used in the initial config because we need to modify
# the Xen config file before restarting when the install is complete.

cat >> $CONFIG << EOL
name="$NAME"
memory=$MEM_SIZE
disk=['phy:$VG/$LV,xvda,w']
vif=['bridge=xenbr0']
vfb=['vnc=1']
kernel="$IMAGEDIR/vmlinuz"
ramdisk="$IMAGEDIR/initrd.gz"
on_reboot="destroy"
extra="console=hvc0"
EOL

#Launch the VM and connect to console to complete Ubuntu installation.  
xm create /etc/xen/$NAME.cfg -c

#Modify the post-install Xen Config
sed -i '/kernel/d' $CONFIG
sed -i '/ramdisk/d' $CONFIG
sed -i '/on_reboot/d' $CONFIG
echo "bootloader=\"pygrub\"" >> $CONFIG

#Launch the new VM
xm create /etc/xen/$NAME.cfg -c