Thank you! I am a little cautious about proceeding, simply because I am not that familiar with Unraid nor the "New Config" tool, and I cannot lose my data.
From my understanding of the documentation (https://docs.unraid.net/unraid-os/manual/tools/), I would assume that I could make a small test just to familiarize myself with the process. As such, I would:
Move one of the four existing array disk (0QEMU_QEMU_HARDDISK_drive-scsi4 - 10 TB (sdd), that is not the parity disk and EMPTY according to the interface) from its current MB SATA-port to the Perc H310.
After boot, create a new config with "keep all assignments" although one drive would be missing, Click "Apply".
Return to main-tab, where I then assign the missing or danling disk ( previously: OQEMU_... - 10 TB (sdd), and now: WDC_WD100EFX..._<disk_serial> ) to its original position in the array.
Then, I am unsure about whether, "Parity is valid", should be checked or not?
My logic is: It is the same drive - that has been moved - and consequently changed name. I would assume that formating, partioning, etc is unchaged from my otherwise sparse knowledge of linux and how unraid operates.
Start the array. Check that all looks good.
Proceed with the next drive, that would have important files.
Repeat with third drive - also having important files.
And lastly, the parity drive.
FINISHED.
It was not clear to me from the documentation, how to safely perform this kind of migration. Quite possible there is a much smarter way?
Thanks, appreciate your help.