I have an RN104 4 bay 2T in each Bay on a Raid 5 set up
I had one drive degraded and put a new one in but it failed to build
Have just moved house and on restart the raid did not mount. After a reboot it did and i started a back up got half way through that and its failed with about 1.5TB of missing data
tried the reboot and no luck
RAIDar diagnostic is showing some errors
Disk 2 has 664 Pending and uncorrectable sectors
it has created 2 vloumes where i only had 1 before and
md/Raid:md127?failed to run raid set
and a mount and unmount action
any suggestions on how to get the raid back so i can get the rest of my data recoverd would be really apprecated have attached pdf of diagnostic for the full story
Starting a re-sync with a replacement drive and another with that many errors without first making a data backup was a big mistake. Unfortunately, it may be one that resulted in data loss because your volume is not redundant during the re-sync and a failure of any other drive can (an apparently did) damage or even destroy your volume during that process. You should also use the full admin GUI, not just RAIDar in making any decisions.
Whatever you do, do not attempt to put the original Drive 1 back in. If it still works at all, it could be of some help in data recovery.
The NAS is showing data and data-0 because it sees some of your drives as a partial volume and some as another, both with the same name, which is not allowed. data-0 is the name of the MDADM RAID on which the BTRFS volume resides, so it's using that for one name. That's probably the new drive and won't show up if you boot without that one So, the first thing to try is booting the NAS with just the original 3 drives in read-only mode (controlled via the boot menu). If that works, make a backup right away
Unfortunately, if that fails, it is rarely successful to try and mount the array manually when the automatic mount fails, so you are likely looking at a data recovery situation. Netgear does offer data recovery, but it's expensive. Software such as ReclaiMe and Home NAS Recovery may help if you have a way to connecting the drives to a PC, but they are also not cheap. Both will allow you to assess your chances of recovery before you shell out the cash. ReclaiMe has been used successfully by other forum users. Home NAS Recovery is a newer player, and I have not seen anyone come here who has tried it. But it claims to do a better job with a damaged volume.
