I've been running a 214 with dual 4TB HGST Nextar NAS drives for a couple of months now. We just had a power outage and when the system came back up it was showing a degraded data status and only seeing Disk 1 in the RAID config (yes I know I should have a UPS on the system). I rebooted the system and when it first came back up it saw Drive 2 and said it was re-sycning. Then it lost Drive 2 again and said re-sync failed and is still in a degraded state. I can still access all files on disk 1.
I removed Disk 2 and put it in a USB external enclosure and connected it to my MAC. Disk Utility recognizes the drive but not the format type. It shows as a GUID Partition, and when I run First Aid on the disk all it says is "Problems were found with the partition map which might prevent booting."
Is this disk history or is there a chance of saving it? If I can save it, how should I format it? I assume I use the GUID Partition setting, but what about format? MsDOS (FAT)? ExFAT?
If it's not possible to save it and get it back into the RAID config I will just erase the data with any type of partition and take it back and exchange it.
Model: RN21400|ReadyNAS 214 Series 4- Bay (Diskless)
Normally, the volume is degraded when you remove a disk. What that means is that the volume can not recover from another disk failure. It is an expected behavior with XRAID with single redundancy that can only protect against loss of one disk - and when you removed the drive, you lost one. In your case, I guess one disk failed which probably is the disk 2.
Are there just 2 disks and not 4? What is the RAID level that it has been using before you removed the disk? I think XRAID RAID1, correct me if I am wrong. If you can still access the files, I strongly suggest to back up the data. After all, it is not a good idea to store important data to just one device.
Yes I realize that disk 2 is bad and it's not a good idea to run non-redundant for any extended period of time. My question is, how do I reformat disk 2 prior to reinsterting and hoping it successfully re-syncs with the array? I have always only run 2 disks, but plan on adding two more, as well as a completely separate RN214 with its own disks that I will use only as a backup array to my primary.
So my question is, how do I reformat the failed drive to see if I can get it back into the array? GUID partition I assume, but what about the file system? Is it MsDOS (FAT), ExFAT? I have no idea how these drives come formated from HGTS. They are specifically designed for NAS RAID.
When you format the disk using a computer and you insert it to the NAS, the NAS will detect that it has volume. You need to let the NAS format it instead which means factory reset. So, the best way is since you still have access the to the files while disk 1 alone is inserted, have full backup of the files first. Then factory reset with the 2 disks inserted. This will format the 2 disks and will let you create a new volume.
Ok so it sounds like a factory reset is my best option. I'll back up my data and get ready to do this. Rigth now my problem is that the ReadyNAS won't even recognize disk 2 so I'll need to put some kind of format on it anyway just for the RN214 to actually see it.
You could try deleting the partitions on the drive and re-inserting it, but I can't help you do that on a Mac. But it sounds like the drive is toast and that's not going to bear fruit.
