Set default architecture (without passing --platform)?

[jeliker1]

I have been happily using podman to create fnproject.io deployments until this week. The issue is that the build is for arm64 (which is my local machine Mac M4) though previously I was building amd64 without doing anything special.

Frankly can't tell what changed except possibly a version upgrade for podman. Is all very perplexing as I don't find any reference to this behavior changing (even if it is version related).

Any recommendations how to set a default build architecture such as you would set with --platform since the fn executable doesn't support passing through parameters like that. It can pass build-args but I've not found anything that will set the build target architecture. Thank you for any advice.

Jon-Eric

[flouthoc]

I don't think there is any method in buildah to change the default platform for builds, default platform is picked up from the host OS automatically. You would need to pass --platform if you are planning to for arch other than the default host.

I guess you can open a feature request to allow setting platform by default to some other value than host.

[jeliker1]

Well no luck. I tried running a amd64 image but it fails from vfkit error. I did confirm that I can run the default podman machine then pull images with --platform=linux/amd64 and successfully run those. Still the issue remains that I can't force podman to build with linux/amd64 without passing the --platform directive and thus cannot build for amd64 when using fnproject fn build command. Argh!

[jeliker1]

Fully removed Podman and installed Docker after two years away. Had the same issue but Docker supports environment variable:

DOCKER_DEFAULT_PLATFORM=linux/amd64

Set that and problem solved! I wish it was obvious why all was well with Podman before the latest update. Simple answer for me would be if there was such a thing as PODMAN_DEFAULT_PLATFORM or similar method to set globally. Here's hoping…

Thank you all for your feedback and guidance!

[flouthoc]

I think we can add this as a feature, this looks like a small change.

[rhatdan]

Should be done through containers.conf And Podman would need to support it as well.

[flouthoc]

I created issue from this disscussion, we will track it here #25641