Image Names

An image name selects the distribution, the release and the architecture of a new VM instance. Pass it to cubic create and cubic run with --image, or set image in a Template File. cubic images lists everything that is available.

Format

distro[:name][:arch]

Part

Description

distro

Name of the distribution, such as debian. Mandatory.

name

Release, given as a version, a codename or a tag. Defaults to stable.

arch

amd64 or arm64. Defaults to the architecture of the host.

Examples:

Name

Meaning

ubuntu

Newest long term release of Ubuntu for the host architecture.

ubuntu:26.04

Ubuntu 26.04 by version.

ubuntu:resolute

The same release by codename.

ubuntu:latest

Newest Ubuntu release, long term or not.

debian:trixie:arm64

Debian trixie as an arm64 guest.

archlinux:rolling

Arch Linux, which has one rolling image instead of releases.

A guest only runs with hardware acceleration when its architecture matches the host. Cubic starts a guest of the other architecture in software emulation, which is much slower.

Tags

Every distribution has the tags stable and latest. Cubic derives them from the release list each time it reads the image list, separately for each distribution and each architecture, so a tag never goes stale and is never cached.

Tag

Meaning

stable

Newest long term release. Distributions without long term releases use their newest release. This is what a bare distribution name resolves to.

latest

Newest release, whether it is long term or not.

rolling

Version of a distribution that has no releases at all. It carries both stable and latest.

Ubuntu is the only distribution with a long term rule of its own. A release is long term when it was published in April of an even year, so ubuntu gives you the last LTS while ubuntu:latest gives you the newest interim release.

Distributions

Name

Releases

Source

Checksum

almalinux

versions

raw.repo.almalinux.org

SHA256

archlinux

rolling

geo.mirror.pkgbuild.com

SHA256

debian

versions and codenames

cloud.debian.org

SHA512

fedora

versions

dl.fedoraproject.org

SHA256

gentoo

rolling

distfiles.gentoo.org

SHA256

opensuse

versions

download.opensuse.org

SHA256

rockylinux

versions

dl.rockylinux.org

SHA256

ubuntu

versions and codenames

cloud-images.ubuntu.com

SHA256

Cubic downloads the official image from the mirror of the distribution and verifies it against the checksum the distribution publishes next to it. See Security for what that protects against.

Cached Images

A downloaded image is shared by every VM instance that uses it. cubic images shows which ones are cached. File Locations names the cache directory and the file name of each image.