Now that you can see the iSCSI device we can create partitions for the virtual machine to use. We just need to create the simplest of patitions, one for the root file-system of the virtual machine and one for swap. You can use fdisk or cfdisk for this, or any other partitioning programme. Your partitions in fdisk might look something like this:
dangermouse:~# fdisk /dev/iscsi_0 Command (m for help): p Disk /dev/iscs_0: 60.0 GB, 60011642880 bytes 255 heads, 63 sectors/track, 7296 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/iscsi_01 1 249 2000061 82 Linux swap / Solaris /dev/iscsi_02 250 7296 56605027+ 83 Linux
Now that we have created the partitions we need to create file-systems on them.
dangermouse:~# mkswap /dev/iscsi_01 Setting up swapspace version 1, size = 5115 kB no label, UUID=055d2ab4-d2ab-4779-818c-71d4950c08df dangermouse:~# mke2fs -j /dev/iscsi_02 Filesystem label= OS type: Linux Block size=1024 (log=0) Fragment size=1024 (log=0) 1256 inodes, 5000 blocks 250 blocks (5.00%) reserved for the super user First data block=1 Maximum filesystem blocks=5242880 1 block group 8192 blocks per group, 8192 fragments per group 1256 inodes per group Writing inode tables: done Creating journal (1024 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 28 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override.
I am going to create a Debian virtual machine using debootstrap.
dangermouse:~# mount /dev/iscsi_02 /mnt dangermouse:~# debootstrap sarge /mnt I: Retrieving Release I: Retrieving Packages ......
Once debootstrap is completed we need to setup the machine a
little bit. We need to disable tls again, setup the
/etc/fstab and the network interfaces and create
tty and console devices. We also need to copy the kernel modules to the
dangermouse:~# mv /mnt/lib/tls /mnt/lib/tls.disabled dangermouse:~# cat <<! > /mnt/etc/fstab # /etc/fstab: static file system information. # # <file system> <mount point> <type> <options> <dump> <pass> proc /proc proc defaults 0 0 /dev/hda1 none swap sw 0 0 /dev/hda2 / ext3 defaults,errors=remount-ro 0 1 ! dangermouse:~# echo "virtaul01" > /mnt/etc/hostname dangermouse:~# cat <<! >/mnt/etc/network/interfaces auto lo eth0 iface lo inet loopback iface eth0 inet static address 192.168.1.10 netmask 255.255.255.0 broadcast 192.168.1.255 network 192.168.1.0 gateway 192.168.1.254 ! dangermouse:~# cd /mnt/dev dangermouse:/mnt/dev# ./MAKEDEV console tty1 tty2 tty3 tty4 tty5 tty6 dangermouse:~# cp -a /lib/modules/`uname -r` /mnt/lib/modules dangermouse:~# umount /mnt
Make sure you unmount the disk ready for XEN to run the machine. If you don't you will destroy the filesystem.
Now that we have a basic Debian machine ready, we need to setup the XEN virtual machine config file. This file needs to be on both clients, buggles and dangermouse.
dangermouse:~# cat <<! >/etc/xen/virtual01 kernel = "/boot/vmlinuz-2.6.16-1-xen-686" memory = 128 name = "virtual01" vif = [ 'ip=192.168.1.10' ] disk = [ 'phy:/dev/iscsi_02,hda2,w','phy:/dev/iscsi_01,hda1,w' ] root = "/dev/hda2 ro" extra = "2" ramdisk = '/boot/initrd.img-2.6.16-1-xen-686' !
Now that we have a config file lets try starting the virtual machine on both of the clients one after the other, shuting it down each time.
dangermouse:~# xm create -c virtual01
This command should produce what looks to be a machine booting, and hopefully it will get all the way to the console where you can log in as root. Once logged in, shut the machine down in the normal way, eg shutdown -h now.
Celebrate! Well done we have a working XEN virtual machine, also known as a domain U. Now repeat the xm create -c virtual01 command on buggles (the other client) to ensure everything is setup and working on there. In each instance test you can ping the ethernet interface from a remote machine.