Excerpts from the presentation referenced by Dave Dykstra are appended. 
There are multiple questions one may raise by reading the presentation; 
below are my initial questions.

1.  Fermilab and the non-CERN HEP community are not part of the Linux 
Future Community analysis as far as I can read, but are consulted later 
after the analysis is prepared (for HEP or CERN internal)?

2. CentOS Stream 8 repositories -- are these available outside of CERN? 
Outside of HEP?

3. Note CC7 not SL7.  What are the differences?

Start Excerpt.

CC7 (CERN CentOS 7) continues to be a supported operating system•
C8 (CentOS Linux 8) is available as a supported operating system

Users of CentOS SIGs (Special Interest Groups) will have no choice but 
to move to Stream (OpenStack, etc)

Factors affecting CERN for LHC Run313•
Both CC7 and CS8 distributions stop being supported mid Run3•
CERN IT Security will permit a small subset of firewalled hosts to 
utiliseCC7 or CS8 until the end of Run3•
Partially upgrading some resources to CS9 during the Run or during one 
of the “end of year stops” may be feasible for some workloads (e.g. WLCG)•
A decision on the successor of CC7/C8/CS8 needs to be made as soon as 
possible to allow experiments adequate time to plan for Run3

Linux Future Committee
Membership is internally comprised of representatives of key business 
units of CERN

Future Linux distributions will be RPM based•
Efforts required for retraining and retooling are too high to move away 
from RPM•
Future Linux distributions will need to support both x86_64 and aarch64•
Many (several thousand) SoC systems will soon come online with aarch64
[NB: aarch64 is 64 bit ARM, such as is used (I believe) in Fujitsu Fugaku]
CERN, Fermilab and other scientific sites are strongly interested in 
common roadmap(s)
Provide CentOS Stream 8 
repositories:•http://linuxsoft.cern.ch/cern/centos/{s8,s8-testing,s8-snapshots}
Long-term: 31.12.2021 onwards•
Drop support for CentOS Linux 8•
Support CentOS Stream 8 (until end-of-life 31.05.2024)•
Support “Next” Linux Operating system
Based on the analysis from the Linux Future committee, collaboration 
with Fermilab and other HEP communities, as well as the WLCG -decide on 
the path forward

End excerpts

Yasha Karant


On 5/3/21 2:14 PM, Dave Dykstra wrote:
> Here's a presentation at HEPiX'21 from CERN that's publicly available:
>      https://indico.cern.ch/event/995485/contributions/4256466/
> My summary was much more succinct than the presentation and is partly my
> own interpretation.  The presentation lists a whole bunch of options and
> basically says that they're sticking with something related to RHEL,
> will decide later which one, and in the meanwhile we can use CentOS 8
> until the end of this year or CentOS 8 stream.
> 
> Dave
> 
> On Fri, Apr 30, 2021 at 05:03:20PM -0500, John R. Dennison wrote:
>> On Fri, Apr 30, 2021 at 09:35:02PM +0000, Dave Dykstra wrote:
>>> Both Fermilab and CERN have stated that they plan to use CentOS 8 stream
>>> for now (or Scientific Linux 7 or CentOS 7) and will evaluate later
>>> whether or not to switch to one of the clones.
>>
>> Can you please provide a citation for this?  The last I recall hearing
>> was what Konstantin referred to - that an official statement from
>> CERN would be forthcoming in Q1 of this year but I have yet to see such
>> a statement and am wondering if, perhaps, I overlooked it somehow.
>>
>> Thank you,
>>
>>
>>
>>
>> 							John
>> -- 
>> "Be polite, be professional, but have a plan to kill everybody you meet."
>>
>> -- General James "Mad Dog" Mattis