Apple Charging Policy

securityguy

If you think the drive is OK, buy an enclosure for a tenner, stick the disk in it, and use it as the destination for the Time Machine backups you're now going to be keeping. Silver linings and that.

Big_Graeme

securityguy wrote: »

It's possible. it's also possible the drive was on its way out, and will work for a while after being powered off for a while, but will stop working fairly soon once it warms up. A common trick for recovering data from suspect drives it to put it in the freezer for a few hours, then fire it up: often they work for a while, long enough to read the data off. That'll be especially true in a Mac as although the disk bay on an iMac is perfectly within the specifications for the drive it is at the upper end thermally, so drives which are unhappy in an iMac might work for a while laid out loose on a desk hung on the end of test cables.

Wouldn't SENSE and proper disk diags pick up any issues like this?

almillar

You mean SMART? No matter how hard it tries, it's never given me an early diagnosis of an immintent (or current!) drive failure, and my own ears work better for this. Macs do use SMART BTW...

Mr_Toad

securityguy wrote: »

It's possible. it's also possible the drive was on its way out, and will work for a while after being powered off for a while, but will stop working fairly soon once it warms up. A common trick for recovering data from suspect drives it to put it in the freezer for a few hours, then fire it up: often they work for a while, long enough to read the data off. That'll be especially true in a Mac as although the disk bay on an iMac is perfectly within the specifications for the drive it is at the upper end thermally, so drives which are unhappy in an iMac might work for a while laid out loose on a desk hung on the end of test cables.

You might like to use something like iStat Pro to look at the drive temperatures; it's also possible that you've got a slow/dusty/whatever fan.

One of the tricks we used years ago when disks in servers went faulty was after they'd been replaced we'd give them a sharp tap on the bench and they would often work long enough to recover the data.

bod1467

Mr_Toad wrote: »

we'd give them a sharp tap on the bench and they would often work long enough to recover the data.

Provided that the sharp tap itself didn't cause a degree of demagnetising of the disc platters.

gjchester

Big_Graeme wrote: »

Wouldn't SENSE and proper disk diags pick up any issues like this?

Depends on the failure.

SMART tracks parameters that generally are down to wear and tear, basically as a drive gets older and it starts to degrade SMART can track that.

As an example it track how long from the power on to the drive spinning at the right speed, as the motor ages this gets longer and is a prediction of failure.
Similarly it can track extreme event so say a temperature highpoint, get a drive too hot and it will fail.
It can also track "normal" faults, All drives have a few bad sectors and have spares to "swap in" If for example you have 100 "spare" sectors when the drive is new then its not unusual to have some of these spares mapped to in use after a few years. Smart can track and warn you when the number of spares hits a low point, So lets say when it gets to 10 left you get an alert so you have time to save your data before there are no spare sectors to swap in and you loose data.


Most drives fail for mechanical reasons, and what SMART can't predict is when exactly that motor that's taking longer to spin up just decides to give up and, or if suddenly there's some problem and the drive need 150 spare sectors but only has 100 available, or the electronics die due to a power spike.

Used correctly its an early indicator of a potential failure, but its just that a potential warning. Drives fail without warning, systems may have has turned off the warnings or the owner may choose to ignore the errors.

gjchester

almillar wrote: »

No matter how hard it tries, it's never given me an early diagnosis of an immintent (or current!) drive failure, and my own ears work better for this.

Its great in noisy server rooms when you can't hear just one drive

That said its only useful if you act on it and replace the drive, or at least have a spare on hand for the time it fails..

Big_Graeme

almillar wrote: »

You mean SMART?

I did, no idea what I was thinking.

gjchester wrote: »

Depends on the failure.

SMART tracks parameters that generally are down to wear and tear, basically as a drive gets older and it starts to degrade SMART can track that.

Yup I understand that wouldn't the drive manufacturer's own diags pick up on overtemp errors and bad blocks/sectors?

We use Hitachi DFT and Lifeguard and it seems to spot these faults.

gjchester

Big_Graeme wrote: »

Yup I understand that wouldn't the drive manufacturer's own diags pick up on overtemp errors and bad blocks/sectors?

It should, but how often would anyone run them when the tools are not available for a MAC and you have to put the drive in a PC to check.

Its still not clear what the original issue was, its possible the bad sectors of the OP were in areas that the OS resided, hence the ability to get the data out, Or the drive is (as has been suggested) failing but not fully dead yet...

Mr_Toad

The original issue seems to have been with the Seagate 1TB drive. Apple identified a problem and started a replacement program.

I had the HDD in my iMac replaced as part of the program following an email from Apple even though at the time it showed no sign of any problems.

I wonder how many people ignored the recall on the basis that there was nothing wrong at the time only to regret that decision later if the drive did actually fail?

I can't find the article on the Apple site but there are details on one of the Mac forum sites.

http://www.macrumors.com/2012/10/19/apple-notifies-imac-owners-of-expanded-seagate-hard-drive-recall/