Building a multi-arch manifest list from a Containerfile¶

Assuming the Containerfile uses RUN instructions, the host needs a way to execute non-native binaries. Configuring this is beyond the scope of this example. Building a multi-arch manifest list shazam in parallel across 4-threads can be done like this:

    $ platarch=linux/amd64,linux/ppc64le,linux/arm64,linux/s390x


    $ buildah build --jobs=4 --platform=$platarch --manifest shazam .

Note: The --jobs argument is optional, and the -t or --tag option should not be used.

Assembling a multi-arch manifest from separately built images¶

Assuming example.com/example/shazam:$arch images are built separately on other hosts and pushed to the example.com registry. They may be combined into a manifest list, and pushed using a simple loop:

    $ REPO=example.com/example/shazam


    $ buildah manifest create $REPO:latest


    $ for IMGTAG in amd64 s390x ppc64le arm64; do   


              buildah manifest add $REPO:latest docker://$REPO:IMGTAG;   


          done


    $ buildah manifest push --all $REPO:latest

Note: The add instruction argument order is <manifest> then <image>. Also, the --all push option is required to ensure all contents are pushed, not just the native platform/arch.

Removing and tagging a manifest list before pushing¶

Special care is needed when removing and pushing manifest lists, as opposed to the contents. You almost always want to use the manifest rm and manifest push --all subcommands. For example, a rename and push could be performed like this:

    $ buildah tag localhost/shazam example.com/example/shazam


    $ buildah manifest rm localhost/shazam


    $ buildah manifest push --all example.com/example/shazam