WD40EFRX stopped working

[Puppetnation]

Hello everybody,
I used to run a QNAP NAS with 4 HDD, all WD RED WD40EFRX.
A couple of days ago my NAS reported disk 3 of 4 starting to have delays (with recommendation of arranging a data backup)

I took the disk out of the NAS and plugged it on a pc with HDD Regenerator to evaluate damage, which reported some delays and even some bad blocks at initial sectors.

At the second HDD Regenerator pass it has stopped working (I was away, letting the pc doing the job) and once back I've found the message "DRIVE NOT READY"...

From that moment this drive is no more detected.

It spins, heads make the usual friendly startup noise but suddenly it starts producing a rhythmical crawling noise like a [fh, fh, fh, pause, fh, fh, fh, pause] and so on... not a click or some percussive noise, it's gentle like a pencil drawing a line on paper.

I guess there is a physical problem... any idea?

Many thanks for your time
GM

[northwind]

HDD Regenerator was a terrible, terrible idea.

You forgot to mention what's your purpose? I suppose, since QNAP told you that some drive is failing and suggested you do a data backup, you did, didn't you?
If you did, then just replace the failed drive, have QNAP re-configure the drives, copy your backed-up data to their place and move on.
If you didn't, then you need to recover the array using 3/4 of the drives, then move to step 1 above.

[Puppetnation]

Perfectly agree HDD Regenerator has overstressd the disk more than it was itself.
I suppose initial sectors were unreadable resulting in a difficult or even impossible drive recognition.
Purpose is NAS, as mentioned in my firts post, configured as JBOD so, no redundancy (don't blame on me) A 3/4 of drives recovery resulted in a 300 mb recovered data of 14+ TB total archive.

Luckily, after 15 minutes after plugging it into a sata-to-usb adapter (2A PSU) it stops making that noise and gets visible to Windows! Drive stayed attached to it so long because I was looking for a mic+preamp to record its noises to be shared to ask for help. It was faster than me.

With a dual-bay sata-to-usb docking (with a 3A PSU) it only takes a couple of minutes to be recognized by Windows... So I started a 4/4 drives raid recovery and IT WORKED!!! Approx. 90% of data was read and most important stuff copied in a safe place.

I'm not an HDD tech guy but I suspect it's a question of demagnetized initial sectors delaying drive recognition (maybe that noise is caused by unsuccesful read attepts) but also a power supply issue too. The most important thing is derive is not dead, sure it's under agony but still readable, I must be quick I suppose with the next whole archive recovery).

I've been really lucky, I know.
But that noise is still digging in my mind... maybe someone has a suggestion/explanation?

Many thanks
GM

[northwind]

Glad it worked, you got lucky.

That sweeping noise is from the attempts the drive is making to read certain sectors.
It's probably due to media damage. A scan with victoria will give you the answer.

[Puppetnation]

I managed to get approx. 96% of data recovered, thanks to a software tool very useful and flawless in rebuilding my RAID volumes (even if JBOD it needs to be reconstructed).
Now my data is safe, a couple of new hard drives are coming.
Lesson learned.

Thanks for your time guys...