On Fri, Dec 25, 2020 at 4:11 AM Simon Matter <simon.matter at invoca.ch> wrote: > > > On Thu, Dec 24, 2020 at 10:21 AM James Cassell > > <fedoraproject at cyberpear.com> wrote: > >> On Wed, Dec 23, 2020, at 9:25 PM, Mark Mielke wrote: > >> > This is an interesting point. Oracle UEK R6, as used in OL 7 and OL 8, > >> > is tied to Linux 5.4.17, and I think the above might be a good summary > >> > of why this is a good thing. One part of this is to set the > >> > expectation for what kABI is supported. The other part is to gain > >> > access to newer features, and reduce the cost of maintaining a high > >> > quality back port that still adheres to this kABI. By deploying Oracle > >> > UEK R6 simultaneously to both OL 7 and OL 8, they have effectively > >> > separated the kernel from the OS distro, allowing for both elements to > >> > be achieved. This seems like something that could be useful to do for > >> > the broader EL community. > >> Red Hat already does this in effect, supporting RHEL 6,7,8 user spaces > >> on RHEL 7 and 8 kernels, via containers. > > > > I'm not sure if I follow your reasoning... If you are saying that > > "this permits somebody to run Linux 5.4.17 on the host, and the user > > spaces can be provided by containers", then sure. But, that's not > > really what Oracle UEK R6 is. With Oracle UEK R6, you can "yum install > > kernel-uek" on either OL 7.9 or OL 8.3, and in both cases, you will > > get Linux 5.4.17 installed that you can boot into, on the host. > > > > Yes, the userspace is often resilient to changes in kernels - that's > > how containers generally work well, and that's how Oracle UEK R6 can > > be so easily applied against an EL 7.x or EL 8.x machines, but > > actually providing a choice of different kernels to use, is not > > something that RHEL provides today (at least not something that comes > > to mind for me, although perhaps I'm missing some specialty > > repository, such as RHE-V?). > > > > As for Oracle UEK kernels, the UEK repo also includes some updated > packages which replace the original distro packages to make things work. > > If you don't need UEK you can remove the UEK kernels, disable the UEK > repos and do a distro-sync to have a clean again. > > Regards, > Simon A "distro-sync" isn't enough. You need to replace *every single RPM*, and pray that no RPM's have tweaks in the ir '%script' operations that are not idempotent. It's actually not a bad bet: I've done it for RHEL, CentOS, and Scientific Linux hosts to pull the host off of or onto a license.