debootstrap

Base element for creating minimal debian-based images.

This element is incomplete by itself, you’ll want to use the debian-minimal or ubuntu-minimal elements to get an actual base image.

If necessary, a custom apt keyring and debootstrap script can be supplied to the debootstrap command via DIB_APT_KEYRING and DIB_DEBIAN_DEBOOTSTRAP_SCRIPT respectively. Both options require the use of absolute rather than relative paths.

Use of this element will also require the tool ‘debootstrap’ to be available on your system. It should be available on Ubuntu, Debian, and Fedora.

The DIB_OFFLINE or more specific DIB_DEBIAN_USE_DEBOOTSTRAP_CACHE variables can be set to prefer the use of a pre-cached root filesystem tarball. Setting DIB_OFFLINE may cause other element to use cached data, while DIB_DEBIAN_USE_DEBOOTSTRAP_CACHE only functions in the debootstrap element.

The DIB_DEBOOTSTRAP_EXTRA_ARGS environment variable may be used to pass extra arguments to the debootstrap command used to create the base filesystem image. If –keyring is is used in DIB_DEBOOTSTRAP_EXTRA_ARGS, it will override DIB_APT_KEYRING if that is used as well.

The DIB_DEBOOTSTRAP_CACHE variable can be used to cache the created root filesystem. By default this is 0 (disabled) and any other value enables this. If run in offline mode then the most recently cached rootfs is used instead of being built.

The DIB_DEBOOTSTRAP_DEFAULT_LOCALE environment variable may be used to configure the default locale of the base image. It defaults to C.UTF-8.

Note on ARM systems

Because there is not a one-to-one mapping of ARCH to a kernel package, if you are building an image for ARM on debian, you need to specify which kernel you want in the environment variable DIB_ARM_KERNEL. For instance, if you want the linux-image-mx5 package installed, set DIB_ARM_KERNEL to mx5.