How can I generate filesystem images that are usable on many different virtualization systems?
- by Mark Longair
I have written a script that generates a root filesystem image (based on Debian lenny) suitable for User-Mode Linux. (Essentially this script creates a filesystem image, mounts it with a loop device, uses debootstrap to create a lenny install, sets up a static IP for TUN/TAP networking, adds public keys for login by SSH and installs a web application.)
These filesystem images work pretty well with UML, but it would be nice to be able to generate similar images that people can use on alternative virtualization software, and I'm not familiar with these options at all. In particular, since the idea is to use this image as a standalone server for testing the web application, it's important that the networking works.
I wonder if anyone can suggest what would be involved in customizing such root filesystem images such that they could be used with other virtualization software, such as VMware, Xen or as an Amazon EC2 instance? Two particular concerns are:
If such systems don't use a raw filesystem image (e.g. they need headers with metadata or are compressed in some particular way) do there exist tools to convert between the different formats?
I assume that in the filesystem, at least /etc/network/interfaces will have to be customized, but are more involved changes likely to be necessary?
Many thanks for any suggestions...
