Hello,
Given that the end-of-life of SL7 is in June 2024, can you please let us know what are the CERN CTA team’s upgrade plans for the post SL7/CentOS7 era? Which it will be your new OS: Rocky 8, Rocky 9 os anything else?
Thanks,
GEorge
Hello,
our current plans are to upgrade to Alma9. We don’t have a fixed date for the migration yet.
CERN Linux team will give support for RHEL and Alma Linux, you can check https://linux.web.cern.ch/ for more information.
Cheers,
Pablo.
Hello Pablo,
Thanks for this. For our reference, can you please let us know why chose Alma instead of Rocky8/9?
Thanks,
George
Hi,
Sorry, can you please also confirm when you are planning to move EOS5/CTA5 on your EOSCTA production instances?
Thanks,
George
Hi @george_patargias ,
We chose Alma9 because it’s going to be the version that CERN will use: Which distribution should I use? - Linux @ CERN
About EOS5/CTA5 in the next weeks we will start to migrate to those versions.
Best regards,
Jorge.
Thanks for the reply Jorge. Will the CTA team at CERN be able/willing to support sites that run CTA on Rocky 8/9? - which is the distro that we seem to be settling on.
George
Sorry, I think we won’t support Rocky 8/9.
Jorge.
Thanks Jorge but could you please confirm with Michael, Julien et all that this indeed will be the case: that you will not be able to support sites running CTA on Rocky 9?
Also, if you could be a bit more precise as to when you will upgrade to EOS5/CTA5 that would be great.
George
Hi @george_patargias ,
I was talking with @mdavis and we will support the OS that are recommended by CERN Linux: RHEL and Alma
In the latest update from the Linux team (9 Aug) says they still plan to support Alma and RHEL. Latest updates - Linux @ CERN
On Wed 13 Sept there will be a presentation at GDB about Linux Future GDB (13 September 2023) · Indico
So officially we don’t support Rocky Linux, because we won’t use it in our machines, but we will give our best effort.
Cheers,
Jorge.
To answer your question about why CERN chose Alma over Rocky, please see the presentation at the Spring 2023 HEPiX workshop, Update on the Linux Strategy for CERN and WLCG (page 8 onwards).
As @jocamare says, the current CERN Linux strategy is RHEL or Alma. As you are no doubt aware, the situation is evolving in the light of RedHat’s decision to change their licensing conditions and there will be an update in a few weeks. But at this stage we don’t expect any change to the CERN strategy.
If you choose to install CTA on Rocky, in principle it should work as the distros are binary-compatible clones of RHEL. However, we will not have a Rocky setup at CERN and will not be able to offer support in case of any problems specific to Rocky.
I hope that answers your questions!
Michael
Hi @mdavis
Many thanks for the HEPIX presentation and the very usefull comments.
According to slide 24, your recommendation to users is to migrate to the 9 familiy (RHEL or AlmaLinux). Do I understand correct, that for the sites that have selected Rocky Linux as the distro to migrate to, that this recommedation should be interpreted as recommendation to migrate to Rocky Linux 9 (rathen than Rocky Linux 8)?
George
Hi George,
The CERN CTA team are planning to go direct to RHEL/Alma 9, so yes, we will skip 8.
As the situation has been evolving, I recommend attending the GDB on Sept 13 for the latest updates (link above).
Cheers,
Michael
Many thanks Michael. I will try and attend the GDB on 13/9.
Best,
George
Sorry, forgot to ask. Can you please let us know the date (if you have one) when you will upgrade to EOS5/CTA5 in your EOSCTA prodcution instances. We need to schedule ours after you.
Best,
George
We will start upgrading our instances to EOS 5 in September. Upgrade of the LHC EOSCTA instances will be deferred until after the end of the Heavy Ion run, so this will take place in November.
Thanks Michael. Can you please let us know to which EOS5/CTA5 versions you will be upgrading to?
If you are going to upgrade to the EOS version that matches the latest CTA5 public release, where exactly I can find the announcements of the CTA public releases?
George
Hello George,
We are still in the process of testing, but the next EOS versions that we expect to upgrade to are 4.8.105 / 5.1.29. We expect to do this in the next couple months.
Regarding the announcements of public releases, we can announce here once they are available.
Best regards,
Joao
Thanks Joao. For my referencm you are currently running CTA 4.10.0-2 in prodcution right?
Which will be yout target CTA version, when you upgrade to EOS 5.1.29? Is it going to be
5.10.0-2?
George
Sorry Joao: can you please confirm the CTA version that will accompany your upgrade EOS 5.1.29?
Many thanks.
Hello George,
Sorry for the late response.
Not all our tagged versions are made into public releases.
We only publish our RPMs for a certain released version after it has been deployed at CERN for a while, and only if we are sure that the risk of something going wrong for other sites is low enough.
At the moment our latest public releases are 4.10.0-2 and 5.10.0-1.
Besides all the new features implemented until that version, it also includes the scripts to upgrade the catalogue from version 12.0 to 14.0.
This catalogue upgrate should have no impact on CTA versions 4/5.10.0-1 but it will be a requirement for any subsequent releases. That is why we decided to release it already.
Internally at CERN we are already using a few versions ahead, mostly due to the need to apply some hotfixes.
However, we have faced some issues with those versions and that is why we haven’t done a new public release yet.
Regarding EOS, we are still using EOS-4 in our LHC instances. We will not be doing any upgrade to EOS-5 there at least while the current run in ongoing.
In other less risky instances we are already experimenting with EOS-5.
However, we found that EOS 5.1.29 has a severe bug on evict logic and should not be used!
If you want to experiment with EOS-5 please use 5.1.28, which is what we deployed on those instances for now.
After we have a new EOS-5 release that fixes this issue, we plan to deploy it here. And then – once have used it and are sure that it is stable enough – we would like it to be accompaining the next CTA public release 
If you have any other questions lmk,
Cheers!
Joao
TL;DR: EOS 5.1.29 is broken with CTA, don’t use it. In the next CTA public release we hope to reference a new (not yet released) EOS-5 version.