Hard Drives - SMART test failure but diagnostics pass

[[R4A]Bigman]

I've recently been having problems with my four Samsung 1TB drives (F1s).

I first noticed some errors being logged by the Linux kernel, so this prompted me to run extended
SMART self-tests on them. All four reported that the test could not be completed as it had found a read error and gave the lba of the error.

To double check, I ran one of the disks through the samsung estool and that confirmed a read error. on returning the drives to scan, they had picked one at random and executed the samsung test, but found no errors. All four disks are back in my possession now.

After running all the smart tests again and also running the samsung test on all four, I found again that all four failed smart but only 3 had errors according to the samsung diagnostics. This confuses me greatly - can any one suggest why this
might be the case? Also, given that the samsung tool has confirmed three disks have errors, what should be my next course of action?

[dirky]

Could be worth trying to RMA to samsung, they definitely sound broken (or atleast dying), which is not what you want to be putting data onto!
http://www.rexo.co.uk/warranty.php
Turn around was around 10-14days for me when I used them a few months ago

[CaptainCrash]

SMART failures are a good enough reason to return a drive, although the exact position with regard to the retailer would depend on how long ago they were purchased. It would probably be quicker and easier anyway to use the manufacturer's own RMA facility, providing the warranty period is still in effect (I'm not sure if Samsung still use Rexo, although the procedure should still be much the same).

I'd be more concerned about *why* all four drives are failing simultaneously - it's not unheard of, particularly if they were all bought at the same time from the same supplier, but it's unusual enough to warrant further investigation. If there's something in the drives' electrical or physical environment which could have harmed them (eg someone kicked the PC while it was powered up), you don't want the same thing happening to the replacements...

[[R4A]Bigman]

Thanks for the info guys.

Status of my drives now:-

1x drive is completely failed -- cannot recover using the Samsung tools, fails Samsung tests
3x drives I've managed to recover and now all pass SMART tests.


Interestingly enough, the drive which passed the Samsung test but was still failing on SMART was rectified by zero-filling the drive (dd if=/dev/zero of=/dev/sda). The others were recovered using the Samsung Low Level Format tool.

I have, however, no idea why or how this worked. All drives still report no reallocated sectors, which suggests the sectors were fine in the first place (which begs the question why they failed in testing)?

Be sure I will be keeping my eye on these drives to ensure they're working correctly over the next few months as I don't like losing all my data.