On 10/4/19 10:34 AM, Robert P. J. Day wrote:

just installed stock centos 8 x86_64 and did "dnf update", now reading up on centos stream, and wondering:

1. can i, at any time, decide to convert this system to centos stream,

notwithstanding any normal updates i've done in the meantime?

Yes .. centos stream contains centos 8 PLUS other things that will be in RHEL 8.x + 0.1.

2. if i'm running centos stream and decide it's just too progressive

for me, can i dial it back to "regular" centos down the road?

Maybe. Once CentOS Stream is fully implemented (not now .. probably a year from now) .. If you move to CentOS Stream, you will be basically running what will be in the NEXT minor version of RHEL (code wise .. so if RHEL 8.1 is released .. stream will contain things based on Source Code for RHEL 8.2). So this means if they were to rebase something to a newer version for RHEL 8.2, when you shift back to the older version in regular CentOS (based in this example on RHEL 8.1 source code) .. will it still run.

The answer is .. it depends. If you rebase a library .. say part of gnome .. then you build something against that (maybe Mate or Cinnamon), then those extra things you built would need to be built again, against the OLDER gnome library, if you shifted back to the older version.

So .. if you installed ONLY items from the main CentOS repositories .. it would be easy to switch between stream and normal.

Switch to stream: dnf install centos-release-stream dnf update reboot

Switch back: dnf remove centos-release-stream rm -rf /etc/yum.repos.d/CentOS-Stream*.repo dnf distro-sync reboot

That would theoretically work if you never added anything outside the main CentOS repositories. Obviously .. IF you add 3rd party repositories or if you build and add other software, you (or the 3rd party repo maintainer) would need to build against the correct versions of the development files for regular CentOS 8 or CentOS Stream 8.