I have problem with HD in my RN102 NAS. When I logged in yesterday to the admin portal of my NAS I saw following error message in the top bar saying: "Detected increasing pending sector: count [122] on disk 2 (Internal) 20 times in the past 30 days. This condition often indicates an impending failure. Be prepared to replace this disk to maintain data redundancy."
As I understand I need to back up all data asap. Currently I have only one HD in my NAS, and the volume is configured for default X-RAID. I already ordered new 3TB WD RED for replacement. I wanted to add new HD to NAS and configure RAID-1, so that all my data is copied from old HD that will probable die soon to new one. My question is how in my circumstances to move safly from X-RAID to RAID-1? Shall I do it in following order:
Step 1. Move from X-RAID to Flex-RAID on old HD to be in JBOD Level
Step 2. Add new HD, NAS should automaticly move to RAID 1 and synch all data.
Is it safe? Will my data be preserved during such operation?
Just leave the NAS in XRAID mode and insert the new disk with the NAS running. However, you should have purchased two disks, and replace the failing one after the RAID volume syncs.
Also, your data is at risk - since disk 1 can fail during the resync process. Ideally you'd back up all the data on the NAS; you should certainly back up anything that is irreplaceable.
Thanks for hint, I did not realize that X-RAID is so flexible solution, I like it! I have just found RAID calculator site: https://rdconfigurator.netgear.com/raid/index.html, it helps me understand which RAID level I will get after adding new drive.
You have mentioned RAID resync process, will it start as soon as new HD is inserted to running NAS?
Can the old HD be removed without stopping NAS, I guess that whithout old HD RAID will be degraded but operational, I will be able to write and read from it?
How will I know that both HDs are in sync and the old one can be removed?
You have mentioned RAID resync process, will it start as soon as new HD is inserted to running NAS?
If the drive is unformatted, the ReadyNAS will run a short disk test, and then automatically add the drive to the array (which starts the resync process). If the drive is formatted, then you need to reformat it via the volume page on the web UI - after that it will add the drive automatically.
Can the old HD be removed without stopping NAS, I guess that without old HD RAID will be degraded but operational, I will be able to write and read from it?
You can remove the old one once the resync is done. As you say, the volume will be degraded but you will be able to read/write from it.
Note that if you had a larger array (RAID-5), then there would be a performance impact, since RAID would be reconstructing data from the missing drive. But RAID-1 is mirrored, so that wouldn't happen in your case. Still, it would be best to keep it as RAID-1 (replacing the failed drive).
How will I know that both HDs are in sync and the old one can be removed?
It will be shown on the log page, and I think there is also a notification (which would show up on the web admin screens generally). It will take some hours to complete (my guess is 12-16). If the exising disk fails completely during the sync (which can happen), the process will fail and you will lose all the data.
I inserted the HD to the NAS when it was power off and power on.
I can see following logs in system > logs tab:
Apr 19, 2019 11:58:10 AM
Disk: Detected increasing ATA error count: [71] on disk 1 (Internal) [WDC WD30EFRX-68EUZN0, WD-WCC4N7TLFDKK] 12 times in the past 30 days. This condition often indicates an impending failure. Be prepared to replace this disk to maintain data redundancy.
Apr 19, 2019 11:58:10 AM
Disk: Detected increasing pending sector: count [697] on disk 1 (Internal) [WDC WD30EFRX-68EUZN0, WD-WCC4N7TLFDKK] 171 times in the past 30 days. This condition often indicates an impending failure. Be prepared to replace this disk to maintain data redundancy.
Apr 19, 2019 11:57:10 AM
Disk: Disk in channel 2 (Internal) changed state from RESYNC to ONLINE.
Apr 19, 2019 11:57:10 AM
Volume: The resync operation finished on volume data. However, the volume is still degraded.
Apr 19, 2019 11:56:09 AM
Disk: Detected increasing ATA error count: [64] on disk 1 (Internal) [WDC WD30EFRX-68EUZN0, WD-WCC4N7TLFDKK] 11 times in the past 30 days. This condition often indicates an impending failure. Be prepared to replace this disk to maintain data redundancy.
Apr 19, 2019 11:55:30 AM
Volume: Volume data health changed from Unprotected to Degraded.
Apr 19, 2019 11:55:28 AM
Volume: Resyncing started for Volume data.
Apr 19, 2019 11:55:08 AM
System: ReadyNASOS background service started.
What is more on status page it is still complaining that the volume degraded.
What can I do about it?
The new HD went from RESYNC to ONLINE in just 2 minutes which is not enough to mirror 300 Gb of data.
What shall I do to force NAS to do "full" RESYNC?
//Wojtek
PS. Sorry for late reply but first drive I recived from shop was broken and I had to wait for replacment,
PS. Sorry for late reply but first drive I recived from shop was broken and I had to wait for replacment,
This one looks broken too - 697 bad sectors and 71 ATA errors since you installed it.
I suggest running WDC's lifeguard software on this disk. That requires you to connect your disk to a windows PC (either USB or SATA). Or maybe find a different supplier.
Hi, I belive disk 1 with bad sectors refers to old hd that was ready present in the nas. Before inserting new hd I had only one drive in RN102 nas. Do you think bad sectors can prevent disks from resync? What can i do to get data mirrored from old hd to new one? /Wojtek
Do you think bad sectors can prevent disks from resync?
Absolutely.
@WojtekW wrote: I belive disk 1 with bad sectors refers to old hd that was ready present in the nas.
That does look right, since the new disk is disk 2.
One approach (in my opinion the best one) is to back up all the data on your NAS. Then do a factory reset with only the working disk in place, reconfigure it, and then restore the data from your backup. One advantage of this approach is that if some files can't be read, you'll know which files you've lost.
A second approach is to "clone" disk 1 to disk 2, using software that can make a sector by sector copy of the existing disk. Then boot up the NAS with only disk 2. This often results in file system corruption (because bad sectors can't be copied), and some of the files often have garbage in them.
The resync you saw in two minutes is the resync of the swap or OS partition. I've been running a lot of expansion experiments and have seen that a lot. It's obviously an error on Netgear's part to report that, as it could be mis-interpreted that the data voume sync is complete.
Aside frome that, yeah, you're original drive was on it's last legs when you started the resync, and resync is hard on a drive.
If you have SSH enabled, exectuting cat /proc/mdstat and btrfs --detail /dev/md127 will help you figure out exactly the condition of the RAID and file system.
