[atomic-devel] Buildah storage

[Chris Negus <cnegus redhat com>]

I posted a question about Buildah storage on an internal Red Hat list. It was suggested that people on the atomic-devel list might be interested in the answer and possibly further discussion. Here it is.

-- Chris Negus

On Thu, Jan 18, 2018 at 11:19:34AM -0500, Chris Negus wrote:
> I saw that "buildah commit" can commit images built by buildah to either containers-storage (which seems to be the buildah default) or docker-daemon (which adds it to the list of images for the local Docker service). I have a couple of questions about that:
>
> 1. Are there other places buildah can commit to (such as CRI-O)?

You can commit an image directly to any location that "buildah push" can
push an image to, and by virtue of buildah using the containers/image
library for reading (pulling) and writing (pushing) images, we've got a
decent amount of flexibility.  There should be a list of examples in the
buildah-push(1) man page.

FWIW, the containers-storage location that buildah uses by default is
the same place that cri-o uses for storing local copies of images, so
images pulled from a registry by either cri-o or buildah, or committed
by buildah, should be visible to both.

> 2. Are there other tools or features other than "buildah commit" that can use those storage types?
> If this is documented upstream, the link to it would helpf since I haven't been able to find it. If not, I'd be glad to help write this up, with some guidance.

Skopeo can, as well as anything that uses the containers/image library
for moving images around, such as podman, but I don't have an exhaustive
list.

buildah-push:
https://github.com/projectatomic/buildah/blob/master/docs/buildah-push.md
skopeo:
https://github.com/projectatomic/skopeo/blob/master/docs/skopeo.1.md
podman:
https://github.com/projectatomic/libpod/blob/master/docs/podman-pull.1.md
https://github.com/projectatomic/libpod/blob/master/docs/podman-push.1.md


HTH,

Nalin

-------------
Chris Negus
Red Hat Principal Technical Writer
RHCA, RHCI, RHCX, RHCE
Author of the Linux Bible, 9th Edition
http://amzn.to/1IBA7NF