On 2026-06-21, Paul Leiber wrote: > I just noticed that I didn't manage to make clear that (1) I don't think that > there is one specific failed partition, but that both partitions containing > databases seem to work, but not at the same time, and that (2) I want to keep > the data on the seemingly failed device. [...]
I used raid for tens of years and never had the problem you described. So I believe it should come from something else than raid failure. raid duplicates data on both partitions. If you don't have a failed partition the duplication is done transparently and quickly (<second). When a partition fails you can add a new and clean partition and the original one, the partition still in raid, is synchronized into it. As others told you you should use smartd to monitor your disks.
