Supermin

supermin - Tool for creating supermin appliances by Richard W.M. Jones (rjones@redhat.com) http://people.redhat.com/~rjones/supermin

Supermin is a tool for building supermin appliances. These are tiny appliances [similar to virtual machines], usually around 100KB in size, which get fully instantiated on-the-fly in a fraction of a second when you need to boot one of them.

A complete description is in the supermin(1) man page.

IMPORTANT NOTE FOR USERS OF SUPERMIN 4.x: supermin 5.x is a rewrite of supermin 4. It is compatible at a high level with supermin 4 / febootstrap 3, but requires some command line adjustments.

IMPORTANT NOTE FOR USERS OF FEBOOTSTRAP 3.x: supermin 4.x is just an evolution of febootstrap 3.x (really we just renamed it). The previous febootstrap program is now called supermin. The previous febootstrap-supermin-helper program is now called supermin-helper. Apart from that they are identical, although they will evolve and add features over time.

IMPORTANT NOTE FOR USERS OF FEBOOTSTRAP 2.x: febootstrap 3.x is a complete rewrite. febootstrap 2.x could only build Fedora distributions. This version can build many varieties of Linux distros. 3.x only builds supermin appliances, it does not build chroots. 3.x does not build cross-distro, cross-release or cross-architecture systems. If you want febootstrap 2.x, please use the 'febootstrap-2.x' branch from the git repository.

Requirements

ocaml

ocaml findlib ("ocamlfind" program)

perldoc - This is just used to generate the manpage.

static libc - Can be replaced with dietlibc, musl-libc (and maybe other alternate libc). See section ``Alternate libc'' below.

bash

gcc

gawk

libcom_err libext2fs /sbin/mke2fs - These are part of e2fsprogs.

For Fedora/RHEL:

rpm librpm yumdownloader (from yum-utils) or 'dnf download' plugin

NB: On RHEL, use yum-builddep supermin' to install all the dependencies. On Fedora use dnf builddep supermin'.

For Debian/Ubuntu:

dpkg apt-get

NB: On Debian, use `apt-get build-dep supermin' to install all the dependencies.

For openSUSE:

rpm librpm zypper

For Mageia:

rpm librpm urpmi & fakeroot, or 'dnf download' plugin

For Arch Linux:

pacman fakeroot makepkg

Optional

These are only needed if you plan to boot the supermin appliances you are building:

qemu >= 0.13 kernel >= 2.6.36

zcat (command) - if your kernel uses gzipped modules

xzcat (command) - if your kernel uses xz-compressed modules

zstdcat (command) - if your kernel uses zstd-compressed modules

Building and installing

If you're cloning this from git the first time, do:

autoreconf -i

For normal builds, and building from the tarball:

./configure make

You can run supermin without installing:

./src/supermin --help

To install the software:

sudo make install

Tests

make check

Note that the tests require a network connection. If you don't have a network connection (eg. for distro package building) then try doing:

./configure --disable-network-tests

Examples

See the examples/ subdirectory.

Feedback and bugs

Send feedback to guestfs@lists.libguestfs.org. You can file bugs in https://bugzilla.redhat.com/ (under "Fedora", "supermin")

Alternate libc

Supermin uses a small, statically linked "init" binary. Normally this is linked to static glibc, but static glibc produces enormous binaries (800KB+). You can use an alternate libc if you prefer. For example, using dietlibc, I can build a 22K init, about 1/40th of the size.

$ ls -l init/init -rwxrwxr-x. 1 rjones rjones 21736 Feb 17 14:03 init/init

• Dietlibc

For dietlibc, build supermin like this:

./configure make clean make -C init CC="diet gcc" make

which builds the init using dietlibc, and then builds the rest of supermin with the dietlibc-using init binary.

• Musl-libc

For musl, build supermin like this:

./configure make clean make -C init CC="musl-gcc" make