Re: Hoping to disable i686 and 32-bit arm for Podman and related tools for existing Fedora releases
On Wed, Feb 08, 2023 at 09:43:19AM -0500, Stephen Gallagher wrote:
On Wed, Feb 8, 2023 at 9:35 AM Daniel P. Berrangé
<berrange(a)redhat.com> wrote:
...
> > Checked with the team and I'm told 32-bit containers on 64-bit arch
> > should not be impacted.
>
> More generally podman can run containers of foreign architectures using
> qemu-user emulation, albeit with an obvious speed penalty. Still this
> has been useful for testing issues on non-x86_64 arches where hardware
> access is hard to come by.
Hold up, this is a really useful tip buried in this thread. Is there a
good howto or example of how to do this? This deserves a Fedora
Magazine or CommBlog article!
AFAIR, assuming you have 'qemu-user-static-XXXX' RPM installed for the
arch you need (which registers the binfmt handlers at boot), there is
not much more to it than passing '--arch $NAME' to 'podman run'
e.g. on my current x86_64 F37 host I can do
$ podman run -it --arch s390x fedora:rawhide
[root@89b49bd5fefd /]# uname -a
Linux 89b49bd5fefd 6.0.8-300.fc37.x86_64 #1 SMP PREEMPT_DYNAMIC Fri Nov 11 15:09:04 UTC
2022 s390x GNU/Linux
[root@89b49bd5fefd /]# uname -m
s390x
one caveat is that if you later run without --arch, I've seen it remember
pick the foreign arch container that's already downloaded, instead of
fetching the native arch container.
Also qemu-user emulation isn't perfect, so if you hit wierd inexplicable
behaviour, QEMU upstream will welcome bug reports...
With regards,
Daniel
--
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