SUMMARY

The ARCC will perform a downtime maintenance window on both Stokes and Newton from August 5-10, 2024 to upgrade from CentOS 7.x to Rocky Linux 8.x.  Anaconda and GCC/glibc will be affected and users may have to re-create/re-compile software they maintain.

DETAILS

What is happening?
The ARCC needs to perform a special one-time maintenance downtime window this summer.  This will be scheduled for August 5-10, 2024.  The primary purpose of this window is to upgrade the Stokes and Newton clusters to Rocky Linux (likely version 8.x).

Why are the clusters switching from CentOS to Rocky Linux?  
Red Hat announced X that CentOS would become an "upstream" product, meaning that it is meant more for testing components for the final release of Red Hat Enterprise Linux itself.  This has caused a need to switch versions of Linux and most clusters are choosing Rocky Linux.  For example, the Texas Advanced Computing Center (TACC) selected Rocky Linux for its Lonestar6 cluster (https://tacc.utexas.edu/news/latest-news/2022/03/01/10-things-know-about-new-tacc-resources-texas-researchers/).  The UCF ARCC reviewed Rocky Linux and found that it would work well.

What has the UCF ARCC done to prepare for the switch to Rocky Linux?
Personnel within the ARCC have been testing Rocky Linux for several months, and have been diligently working to re-compile/re-install newer versions of all software.  The plan is to initially start with later versions of all software only.  However, if your research requires a particular version of software, please do let us know by submitting a ticket with the subject "Rocky Software Re-install" and we will attempt to support such requests (not all software can always run on newer versions of operating systems).

How does this affect Anaconda environments?
All Anaconda environments will have to be re-installed/re-created.  The ARCC will ensure that the system-wide environments previously installed are still available; however, users that maintain their own will have to re-create them.  We will try to release a guide to help.

What about effects to other software?
GCC (glibc) will be updated and you may have to re-compile any software you specifically compile yourself.  We do not believe that other software will be affected other than moving to later versions.

Please let us know if you have any questions!

Stokes and Newton will be taken down per our bi-annual routine maintenance cycle during mid-May. Specifically, the clusters will be unavailable from Thursday, May 9 through Wednesday, May 15, 2024.

The primary objectives during this downtime is to integrate a new user and management nodes on Newton, prepare our old storage server to be final decommissioning, refresh Ethernet switches on the Stokes cluster, perform maintenance on the GPU cluster (Newton), update the SLURM job scheduler throughout both clusters, and perform other tasks we cannot do while the system is operational.

Recall that we routinely bring the system down twice a year, once in late Fall and once in late Spring. We will keep the users notified in advance of such downtimes, but we recommend you build such expectations into your workflow. Though we anticipate no data loss during this time, it's never a bad idea to backup your materials. So we suggest you use this opportunity to copy salient data and code off of Stokes and Newton prior to the downtime