On Wed, Aug 26, 2015, at 05:09 PM, Josh Boyer wrote: > Hi All, > > I'm emailing my questions on the topic here as it seems to be the best > Fedora focused place to discuss Atomic Host and kernel interaction. > If that isn't the case, please point me to where you believe that is. As jbrooks pointed out, there is also atomic-devel@xxxxxxxxxxxxxxxx. Regarding interaction, one thing I'd ask the Fedora kernel packaging team to keep in mind whenever making any changes to the kernel.spec is that ostree takes over kernel installation - we don't use the stuff in %post. The atomic swap of the bootloader configuration is at the heart of the model. Things work OK now, but just something to keep in mind. > I have two basic questions around the interaction of Atomic Host and > the kernel. The first is fairly straightforward: is there anything > Atomic Host or the atomic toolset needs that the kernel does not > provide today? So the ostree side is one thing, but beyond that for Docker, storage and networking are big items. I think conversations on storage for containers are going on elsewhere, but just noting that. > The second question is a bit more involved. Atomic provides the nice > ability for rollback across the entire OS tree. However, that > requires an atomic image to be spun for every instance of that tree. I'd say: "requires an new tree composed to be spun for updated kernels". I use "image" for qcow2, installer ISO, PXE-to-Live etc. The first two support in place upgrades. > That, naturally, means that whenever a new Atomic Host instance is > spun it will use whatever kernel happens to be the latest in the > Fedora release it is built from. This means that one cannot leverage > the nice side effect of being able to update the kernel independently > of userspace. (Which is also nice from a testing perspective when it > comes to kernels and regressions.) Yes, currently, but most limitations around that kind of thing go away with https://github.com/projectatomic/rpm-ostree/pull/107/commits > To my understanding, the only way to provide such testing would be to > create Atomic Host images that only deviate from the official images > in that they provide a new kernel. There's also support for updates-testing: https://fedoraproject.org/wiki/QA:Updates_Testing#Using_it_with_Fedora_Atomic_22 > With a two week image release timeframe though, being able to use > different kernels might be a good idea. Does anyone have any thoughts > around this topic and how to possibly accomplish such testing? The > only other idea I had was to spin the Atomic Host images containing > the last 3 kernels in them, but I am not sure if choosing between them > at boot is currently possible with multiple kernels installed. Having multiple trees that differ only by kernel by default in a single image is indeed possible. It might be interesting to have updates-testing cloud images generated that also have the non-updates-testing content or something like that. Finally of course, don't forget that composing trees is something one can do locally too, it doesn't require magical rel-eng powers. It is an investment to set up, but for those with multiple machines where you want to synchronize state, it could be worth the investment. _______________________________________________ cloud mailing list cloud@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/cloud Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
