Virtualization the Linux/OSS Way

Listing 1. Script to Create Multiple VMs

#! /bin/bash
# A quick and dirty script to create multiple virtual machines,
# give them unique hostnames and IP addresses, and culminate in
# bringing them on-line.

# name of the directory where we'll mount our vdi's
dir=temp
rootdir=`pwd`/$dir

# the basename for the vms
basename=vbox-vm-

# the file that contains the basic disk image
basevdi=base.vdi

# how many images are we making
number=2

# what subnet will these guests be going on
IPnetwork='10.7.7.'
gateway='10.7.7.1'

# the start of the address range we will use
baseIP=10

# amount of memory these guests will get in Mbytes
memory=512

# base VRDP port
baseRDP=16001

counter=1
while [ $counter -le $number ]
do
  echo $basename$counter $basename$counter.vdi \
       $IPnetwork$baseIP $memory
  VBoxManage clonehd `pwd`/base.vdi \
                     `pwd`/$basename$counter.vdi --variant Fixed
  sudo mount_vdi/mount_vdi.sh $basename$counter.vdi $rootdir 1
  sudo sed -i "s/basicsys/$basename$counter/g" $rootdir/etc/hosts
  sudo sed -i "s/basicsys/$basename$counter/g" $rootdir/etc/hostname
  sudo sed -i "s/1.1.1.2/$gateway/g" $rootdir/etc/network/interfaces
  sudo sed -i "s/1.1.1.1/$IPnetwork$baseIP/g" \
           $rootdir/etc/network/interfaces
  sudo rm $rootdir/etc/udev/rules.d/70-persistent-net.rules
  sudo touch $rootdir/etc/udev/rules.d/70-persistent-net.rules
  sudo umount $rootdir
  sudo losetup -d /dev/loop1
  sudo losetup -d /dev/loop0
  VBoxManage createvm --name $basename$counter --register
  VBoxManage modifyvm $basename$counter --pae on --hwvirtex on
  VBoxManage modifyvm $basename$counter --memory $memory --acpi on
  VBoxManage modifyvm $basename$counter \
                      --hda `pwd`/$basename$counter.vdi
  VBoxManage modifyvm $basename$counter \
             --nic1 bridged --nictype1 82540EM --bridgeadapter1 eth0
  VBoxHeadless --startvm $basename$counter -p $baseRDP &
  sleep 5
  baseRDP=$((baseRDP + 1))
  baseIP=$((baseIP + 1))
  counter=$((counter + 1))
done

Resources

Oracle's Virtualization Blog: blogs.oracle.com/virtualization

mount_vdi: www.mat.uniroma1.it/~caminati/mount_vdi.html

Bill Childers' “Virtualization Shootout: VMware Server vs. VirtualBox vs. KVM”, LJ, November 2009: www.linuxjournal.com/article/10528