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Forum Discussion
creifle
Apr 18, 2020Guide
Can I format a previously formatted disk while an xraid volume is in place?
My ReadyNAS 316 contains 2 8TB and 4 4TB drives running X-RAID. All WD Enterprise class drives from the NG Compatibility List. Drive #6 (4TB) began reallocation sector errors which began to increase...
- Apr 18, 2020
Yes, you can replace the failed 4TB with the previously removed 4TB. BUT, if your data is inaccessable, it probably won't help. If your volume is reported as "degraded", then it will. It sounds. however, that you had a second drive fail, in which case the volume will be shown as "dead", and you are in a data recovery situation. That's going to cost, and it's likely not going to be 100% successful. Your recovery options are paid support from Netgear or hookling the drives up to a PC and running ReclaiMe software. Both will require a location to offload the data so you can later destroy the old volume, create a new one, and put the recovered data back.
Of course, if you have a backup (and I assume you would probably not be here asking if you did), you can replace the bad drives, factory default, and restore data from backup.
If the volume is just degraded, you really should think about making a backup before you proceed. Volume re-sync is drive intensive, and any drive close to failure has a higher chance during it. Then, the best way to proceed is to swap the drive with power on, especially for a previously formatted drive. The NAS will tell you you removed and then inserted the drive, and will complain the "new" one has data on it. At that point, you select it and click "format". Don't format it outside the NAS first, it won't help. But you can remove all partitions and avoid the format step when it's inserted in the NAS if you choose.
BTW, the data on the drive from the previous installation on the NAS, it isn't usable since it's an incomplete part of a RAID array..
Sandshark
Apr 18, 2020Sensei - Experienced User
Yes, you can replace the failed 4TB with the previously removed 4TB. BUT, if your data is inaccessable, it probably won't help. If your volume is reported as "degraded", then it will. It sounds. however, that you had a second drive fail, in which case the volume will be shown as "dead", and you are in a data recovery situation. That's going to cost, and it's likely not going to be 100% successful. Your recovery options are paid support from Netgear or hookling the drives up to a PC and running ReclaiMe software. Both will require a location to offload the data so you can later destroy the old volume, create a new one, and put the recovered data back.
Of course, if you have a backup (and I assume you would probably not be here asking if you did), you can replace the bad drives, factory default, and restore data from backup.
If the volume is just degraded, you really should think about making a backup before you proceed. Volume re-sync is drive intensive, and any drive close to failure has a higher chance during it. Then, the best way to proceed is to swap the drive with power on, especially for a previously formatted drive. The NAS will tell you you removed and then inserted the drive, and will complain the "new" one has data on it. At that point, you select it and click "format". Don't format it outside the NAS first, it won't help. But you can remove all partitions and avoid the format step when it's inserted in the NAS if you choose.
BTW, the data on the drive from the previous installation on the NAS, it isn't usable since it's an incomplete part of a RAID array..
- creifleApr 18, 2020Guide
Fantastic answer and GREAT timing.
I worded the NAS performance poorly, it is displaying DATA DEGRADED. And no other drive is showing any sign of failure. However, I am prepared to replace the older ones (4 TBs). So your answer gives great hope. You're assumptions are right on regarding the lack of backup. Yes, I know. Wet noodle lashes.
Funny thing about the backup, I had an old ReadyNAS NV with 6 TB X-RAID volume and was going to set that up to backup the most critical stuff. It hasn't been running for 2 years. Plugged in and touched the power button, lit and immediately went off. Touched again. POP and stink!! So much for the back up plan. LOL
One more question if I may: I had pulled all the good drives (NAS powered off) and inserting only the replacement drive with data. Then I tried to format the replacement to prepare it. But the NAS kept coming back with "Drive Part of a RAID volume." and would not format. Of course, this drive used to be part of the current volume 2 years ago. I then considered performing a FACTORY DEFAULT with the replacement drive in place only. But some nagging voice in me said, "Don't do it." I was concerned that the NAS (diskless) still had some configuration with the 5 good RAID volumes and if I FACTORY DEFAULT, there would be a problem when I migrated the 5 back into place (correct order, of course.)
True or False?
You're advice is greatly appreciated and your teaching a very old dog, new tricks.
- StephenBApr 19, 2020Guru - Experienced User
creifle wrote:
I then considered performing a FACTORY DEFAULT with the replacement drive in place only. But some nagging voice in me said, "Don't do it." I was concerned that the NAS (diskless) still had some configuration with the 5 good RAID volumes and if I FACTORY DEFAULT, there would be a problem when I migrated the 5 back into place (correct order, of course.)
True or False?
All the NAS configuration info is stored on the hard drives. There is a small (4GB) OS partition on each drive - configured as RAID-1 (all drives mirrored). The system boots from that partition. So the answer is false.
The NAS should have let you reformat the drive. Likely it was confused since the drive was once part of the array. If you can connect it to a PC, you could reformat it there (And then reformat again when you hot-insert it into the NAS). If you do a factory default with only that drive in place, I suggest switching to flexraid and destorying the data volume before shutting the NAS down. Then restore all the other drives in place in their slots (leaving the slot for the replacement empty). Then power up the NAS and hot-insert the replacement drive after the boot is complete. You might still need to format it though.
- SandsharkApr 19, 2020Sensei - Experienced User
"Degraded" means you can replace the drive and all will be well, assuming nothing goes wrong during re-sync. At this point, you've just lost redundancy.
There is a reason I told you to insert the drive with the NAS up and running. If you insert it then power up, the NAS will try and fail to figure out what that odd drive from the array is doing there. With the other drives also present, it might boot and it might not.
With that drive alone, since every drive has a mirror of the OS partition, it's booting from that and recognizing that the main partition of the drive is a part of a RAID array, and it's protecting you from yourself by disallowing a format. If you do a factory default, the drive will then have a valid JBOD volume rather than a partial RAID volume, but the results will be about the same when you add it to the array.
So, you can either power the NAS up (with just the three good drives is OK) and then hot insert the drive, or you can use a PC to remove the partitions on the drive, and power up with all 4. I like the first option because the NAS will report and log every step.
If your intent in inserting it separately is to check out the drive because you have no other way, then go ahead and do a factory default on just that drive. But still follow my instructions for adding it to the array. Don't put it and the other three in the NAS and boot unless you've removed the partition table.
Most likely, your NV power supply fried. If that is it, it's fixable by replacing the supply, but Netgear won't sell you one. Even if your supply is in the serial range of the recall and you never got the free replacement, I don' think they have any more. You have to decide if the cost of a third-party supply is worth it. If your NV is as old as mine and does not have the fanless power supply, you can re-wire a standard flex ITX supply and install it. If you have a fanless one, there's a bit more work required and most choose a third party supply with the mods already done. If you decide to try this, it's best to start a new thread.
- SandsharkApr 19, 2020Sensei - Experienced User
Looks like StephenB was in the process of writing a reply when I started mine. Just to make sure you know what he is saying -- you can destroy the volume of the single drive, then it should let you format it, if you still think you need to. With XRAID off, the NAS will not immediately start creating a new volume after the format. That info is storred on the drive, so has no impact when you go back to the original drive set.
I don't know if it was added at some point or if it's always been there, but the ReadyNAS does prevent you from formatting a drive that's part of an active array. And though incomplete, The NAS considers your single drive as an active array.when you boot from it. I've run a lot of experiments on my "sandbox" system that ended up hosing an array, so i have lots of experience with this.
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