Is there anyone out there who can answer my question:
RAID1 in bay 1 and 2. In the last bay, a hotspare disk that simply integrates itself directly into RAID 1 as soon as a disk fails.
Question: Now RAID 1 in bay 1 and in the last bay = unattractive. What happens if I replace the failed disk in bay 2? Does the hotspare then become the hotspare again or does bay 2 become the hotspare? This is a complicated question that I couldn't find out anywhere on the internet. Otherwise I will have to carry out a practical test.
Thanks =)
I can't answer that for the Synology RS1219+ with absolute certainty, as I've only had it for a few weeks and no HD has failed in it so far.
In all likelihood, the Synology RS1219+ will not behave any differently than the Qnap models. If a disk configured as a hot spare is used, it remains active in the RAID. However, the replacement disk for the failed one does not automatically become the new hotspare, but remains unassigned for the time being. I had to manually assign the newly inserted disk to the RAID as the new hotspare. Therefore, over time/years, the hotspare in one of my 8-bay NAS moved through the bays.
This way, the RAID is only rebuilt once with the hotspare, which makes sense because it takes a while (several hours/days depending on the HD storage volume and the type of RAID).
If the replacement disk were to be reintegrated into the RAID and the activated hotspare were to be made into a hotspare again, either several TB would have to be copied or the RAID would have to be rebuilt again - thus causing a very long process a second time, which makes little sense.
Of course, you can force this manually by pulling the spare disk in the last bay after reconfiguring it as a hotspare and making it a hotspare again after reinserting it. However, this also makes little sense, because it causes very long processes twice. I only played this game once about two decades ago. After that, I was able to come to terms with the fact that I don't really need to know which disk is currently hotspare to my RAID6 with 7 active disks. You can see it quickly when you log in administratively.