Ready NAS not responding after resync

Sounds like you have a bad disk.

Can you power down, remove your disks (label order), and check e.g. SeaGate disks with SeaTools and WD disks with WD LifeGuard Diagnostics?

mdgm wrote:
Sounds like you have a bad disk. Can you power down, remove your disks (label order), and check e.g. SeaGate disks with SeaTools and WD disks with WD LifeGuard Diagnostics?

I've noticed that it managed to shutdown. Not sure how. I've pressed the button for a long time, and after I came back a few minutes later it was powered off.
I rebooted it and it did a Quota Check, then managed to send me a few emails (more errors from the same disk) and I eventually got an other email that a resync has just started again. But it does not respond to anything now.

Now: should I try to (re)boot it to perform a backup or just remove the candidate bad disk (it is always the same) and get a new one? Or run a backup without the broken disk?
Unfortunately I do not have any PC to perform the checks, I will trust the emails.

And should I remove the disk while it is powered off or as soon as it boots?

Power off the NAS. Once the NAS has powered off remove the bad disk, turn the NAS on again and see if it boots

mdgm wrote:
Power off the NAS. Once the NAS has powered off remove the bad disk, turn the NAS on again and see if it boots

yes it booted.
seems to be ok.

now either I try to backup or I just switch off and wait for new disk to arrive.

when it is here, should I put it in when it is on or off?

Either should work. My personal preference is to add while the NAS is on. When you add it while the NAS is on the disk should be automatically wiped and added to the array. If the disk is already partitioned the NAS may fail to boot up when you add it while the NAS is off. If the disk is not partitioned and you add it while the NAS is off, it should be wiped and added to the array.

I would use the time to check my backups. If you don't have any updated backups, I'd make sure that you take special care for that in a near future.
I don't think that leaving the NAS on or off will make a difference for the probability of the other disks to die while waiting for the delivery. I believe that more stress is made on disks while booting than while spinning freely.

Well there are arguments both ways about leaving off/on

However you should
Make sure you have an up to date backup
Get a replacement disk ASAP.

I agree with mdgm that generally it is good to hot-insert the replacement disk.

If you don't have a backup, then make one while waiting for the disk to arrive. Then if the array were to fail before the new disk arrives and is synced, you won't lose data.

After the backup completes, if you feel more comfortable switching off the NAS, then go ahead. It shouldn't do any harm. Though if the remaining disks are healthy I'd probably leave it on myself.