First off, you will want to build images on a KVM capable machine. If not, you will be missing out on the hardware acceleration and your install will take forever!

virt-install

This is a command line tool written in python that will allow you to specify the layout of a guest, and do an installation of that guest.

Since the man page for this program contains most information you would want to know, I will keep this section short with just an example and a few quick notes.

The below example will create a 10GB sparse backing file, and start the installation from the ISO image specified in the --cdrom option. The disk is specified as having a bus type of virtio, this is only available if your distro has virtio drivers available. As of SL5.3 (RHEL5.3) the virtio drivers have been backported as well as all necessary software to support virtio(lvm2, etc) upgraded to enable you to use virtio. If you are using SL5.2 or less you must remove the bus=virtio option.

virt-install --connect qemu:///system \
    --os-type linux \
    --os-variant rhel5 \
    --name sl53 \
    --ram 256 \
    --disk path=/home/mvliet/sl53-pvm.img,bus=virtio,size=10,sparse=true \
    --accelerate \
    --cdrom /home/mvliet/SL.53.031809.DVD.i386.disc1.iso

NOTES:

• When creating a KVM guest you must always use the --accelerate option. If you do not, it will fall back to QEMU emulation.
• the --cdrom option can point to an actual drive (ie, /dev/hdc), or a iso file on your local machine, or even a remote file (ftp, http, etc.).
• ram is specified in MB, disk size is specified in GB.
• the --disk option may be of more use to you the --file.

virt-manager

One of the features of virt-manager is the ability to create new guests by using a nice GUI. There are some features you will not have access to with this approach, but the majority of features you need will be there.

virt-clone

This is another command line program that will take an existing guest image and create a copy of it. Assignment of new UUIDs and network MACs is easily handeled here.

-- MattVliet - 04 Mar 2009