There will be a scheduled downtime of the Fritz and Helma cluster
starting at 06:00 on Monday, July 6.
We expect normal operation to resume by the evening that day.
Reason for the downtime is maintenance work on the cooling water pipes in the building. We will also use this opportunity to switch the ‘default’ on Fritz from AlmaLinux 8 to AlmaLinux 9 – see this post for more information on the switch from AlmaLinux 8 to AlmaLinux 9.
As usual, jobs that would collide with the downtime will automatically be postponed until the downtime is over. Most frontends and most fileservers will be available through the downtime. There are exceptions: The workspaces under /hnvme on Helma will NOT be available throughout the maintenance period. And as we’re switching the Fritz-frontends to Alma 9, they will also be partially unavailable during that time.
Reason for the downtime is insulation work on the cold-water pipes.
Update 2026-07-06 15:30: We have been informed that insulation work could NOT be finished today. Unfortunately, that means Fritz and Helma will remain unavailable until some time tomorrow.
Update 2026-07-07 17:00: Fritz is operational again, Helma will be tomorrow in the course of the day.
Update 2026-07-09 10:00: Helma and Fritz (and all other clusters) are currently down because of a security-problem in the Linux-Kernel, see this post for info and updates. However, the maintenance is over, so we’re marking this post as “done” now.