About images

About images

MAAS provides supported images for stable Ubuntu releases, and for CentOS 7 and CentOS 8.0 releases. Other images can be customised for use with MAAS.

This article will help you learn:

What is a MAAS image?

MAAS images are more than just the operating system kernel. In fact, a usable MAAS image consists of at least four things:

  • a bootloader, which boots the computer to the point that an operating system can be loaded. MAAS currently uses one of three types of bootloaders: open firmware, PXE, and UEFI.
  • a bootable kernel.
  • an initial ramdisk.
  • a squashfs filesystem.

If you were to look at the squashfs.manifest, you’d see something like this:

adduser	3.118ubuntu5
apparmor	3.0.4-2ubuntu2.1
apport	2.20.11-0ubuntu82.1
apport-symptoms	0.24
apt	2.4.5
apt-utils	2.4.5
base-files	12ubuntu4.1
base-passwd	3.5.52build1
bash	5.1-6ubuntu1
bash-completion	1:2.11-5ubuntu1
bc	1.07.1-3build1
bcache-tools	1.0.8-4ubuntu3
bind9-dnsutils	1:9.18.1-1ubuntu1.1
bind9-host	1:9.18.1-1ubuntu1.1
bind9-libs:amd64	1:9.18.1-1ubuntu1.1
binutils	2.38-3ubuntu1
binutils-common:amd64	2.38-3ubuntu1
binutils-x86-64-linux-gnu	2.38-3ubuntu1
bolt	0.9.2-1
bsdextrautils	2.37.2-4ubuntu3
bsdutils	1:2.37.2-4ubuntu3
btrfs-progs	5.16.2-1
busybox-initramfs	1:1.30.1-7ubuntu3
busybox-static	1:1.30.1-7ubuntu3
byobu	5.133-1
ca-certificates	20211016
cloud-guest-utils	0.32-22-g45fe84a5-0ubuntu1
cloud-init	22.2-0ubuntu1~22.04.3
cloud-initramfs-copymods	0.47ubuntu1
cloud-initramfs-dyn-netconf	0.47ubuntu1
command-not-found	22.04.0
console-setup	1.205ubuntu3
console-setup-linux	1.205ubuntu3
coreutils	8.32-4.1ubuntu1
cpio	2.13+dfsg-7
cron	3.0pl1-137ubuntu3

This snippet gives you a basic idea of the kinds of things that have to be loaded onto a drive in order for the system to function independently.