degraded RAID 5 volume will not mount
I am running 5.8.4 XT on Catalina. I have a RAID 5 4*5 TB in an OWC TB4 enclosure, with one missing disk (failed) and one out-of-sync disk. I am unable to rebuild or add a replacement disk to the volume due to the out-of-sync disk - fine. I am ready to make a backup and create a new clean volume with certified disks.
However, I am also not able to mount the RAID 5 volume. It says it is mounting, then immediately dismounts. No message in the log as to why. Any hints here?
Tech report is attached.
MacOS attempted to repair the volume after an unclean shutdown. It failed and left the volume marked as unmountable.
You can use Disk Warrior to repair the directory, it can fix it in place.
Or you need a recovery program, like Disk Drill, or R-Studio, to recover the data.
Its possible it may mount again, as macOS auto repair runs every mount attempt, but it is not likely.
I am having what sounds like an identical problem to the one described here. Replaced a failed drive (1 of 6) and now trying to mount volume so it can rebuild. Nothing happens on its own and if I try to manually mount the volume in software I get a blue status bar on the volume icon for a second, and then goes back to original state with the same message "rebuilding, waiting for mount".
I tried repairing the directory in disk utility as recommended above, but the volume is not visible in disk utility, only the individual drives.
Report attached, thanks in advance for your help.
Removed disk, volume still will not mount, shows as the same in disk utility as well. I only mentioned or tried disk utility because that is what the admin suggested in the original post.
Got the same dialog appearing with all on startup both with and without the replaced ssd.
Oops, my apologies. I misread the original post, "Disk warrior", not "Disk utility".
Still need help though. :)
Here you go. This one is without the failed drive or a new drive attached. My original post contained a report with the failed drive still in.
Thanks for your help!
When was the last time this volume mounted?
Are you backed up?
It appears the directory is damaged, you may need to run a data recovery application to recover data from this volume if it is not backed up. (Like Disk Drill or R-Studio)
Last mount was about 12 days ago. This volume is my primary backup, so yes and no. Will try one of those programs to repair the directory, thanks for the recommendations.
In case that doesn't work, is there any reason I can't wipe the drives and rebuild the volume from scratch with the same disks?
A feature/utility that is a part of, or comes with, softraid capable of repairing APFS volumes would be a good update in the near future. Maybe a partnership with one of those companies.
Thanks again for the help.
As of yet, there are no utilities capable of repairing APFS volumes. One of my personal hesitations in using APFS day to day. I have heard that Apple has not yet published the documentation that would allow developers to repair APFS volumes. You can "recover" data, but not fix a volume.
No reason you cannot restore the data, that is your best option.
Thank you, that confirms what I have found as well.
Appreciate the help!