Weird file corruption issue on mac pro

[mirzank]

Hi,

I've got a macbook pro 13 inch 2010. A few years ago i replaced the normal HDD with a kingston SSD. so far so good. No crashes, sleep issues, hangs, etc ever that other people complain about because the kingston uses the same controller and memory chips as the air.

Then recently i used an optibay to replace my optical drive with a 1tb HDD.

Thats when trouble started.

I have an HTPC i copy media files over to. I use a portable usb 2.0 drive to copy files from mac. then copy from USB drive to HTPC. well i noticed a bunch of times i'd copy files over and they would refuse to play. I thought it was a faulty usb drive, i formatteda bunch of times, tried NTFS as well as HFS. same problem. files arent corrupt all the time. but randomly. anyway i thought it was some basic flaw with the usb drive.

So i tried a different usb drive. same thing. the file would play fine on my mac. then i'd copy it over, and it would be corrupt. not all the time. sometmes. i'd copy again sometimes it would be fine sometimes not. mind you not corrupt like the file showing up as 0 bytes like i've seen before, but it would show the full file size as normal. but it just wouldnt play.

as unlikely as it was, i thought maybe it was an issue with video files or a file system corruption. i formatted my computer, started from the basics, from scratch, only restored my media files on a clean 10.8 install. the problem persists.

recently i set my iphoto folder to this optibay drive. everything synced over from my iphone. and then 2 days later, the iphoto library just wont load. it there. the sysem structre is there. i can explore it via show package contents and see that the directories all exist. but it just wont load.

this is driving me bonkers. i dont know if its an issue with the drive, maybe the usb controllers, the optibay, or what. if someone has an idea how i can test this please let me know.

 

[sjinsjca]

How are your various drives formatted and partitioned? What version of OS X are you using? Is FileVault or FV2 enabled on any of the drives in question?

 

[TheBSDGuy]

It sounds like its the cable. Cable problems seem to be surfacing on a lot of these units. Cable problems will act just like HD problems because they can end up generating I/O errors and in some cases if the contact is intermittent during a write operation they'll write junk to the drive.


I use a product called Scannerz. It's the only one on the market that can detect cable or system problems. It does it by using the surface scan progress as a reference. If errors always occur at the exact same place, it's the drive that's the problem. If you're getting I/O errors or timing problems and they're from the cable they'll never correlate to the surface scan. They just occur wherever and whenever they feel like.

You can check out more information on the product below:

http://scsc-online.com/Scannerz.html

You might also want to check out some of the articles in their how-to and downloads sections. Lots of stuff there.

 

[MacRobert10]

If you check on Apple's support web site I think you'll find lots and lots of reports of bad SATA cables. There's at least one such post on this site as well but I don't have the link and didn't bookmark it.

 

[mirzank]

How are your various drives formatted and partitioned? What version of OS X are you using? Is FileVault or FV2 enabled on any of the drives in question?

with my external USB drive it was initially formatted with NTFS. then i reformatted with HFS+ (journaled).
With the optibay i've formatted with ntfs.

i have tried both paragon ntfs and tuxera for writing to ntfs.

i had used both on my macbook pro before these problems started occurring, and never had any problems.

Never enabled filevault.

----------

If you check on Apple's support web site I think you'll find lots and lots of reports of bad SATA cables. There's at least one such post on this site as well but I don't have the link and didn't bookmark it.

i'll look on apple forums to see if i can find the messages.

Now when you say bad sata cable, do you mean to the ssd i use as my primary hdd, or to the optibay harddrive? As far as i remember, neither of them had a cable (atleast not in the way a desktop does), and both just kind of fitted into the sata port.

if my memory serves me right and both have connecters the drives dock into rather than a cable, how would i go about replacing these? a cable obviously is easy to replace but if its a sata port fixed in place i'm guessing i cant do this without paying apple?

 

[sjinsjca]

Well, I've seen the occasional fluky thing happen with NTFS (which is not officially supported) but this sounds like it's happening too frequently and inconsistently to be a software issue like that.

I'm coming around to suspect a cable, as others here have suggested. For the SATA cable, you might try unseating and re-seating it a few times in case it's just an iffy connection. Try a different USB cable too. That Scannerz utility someone mentioned sounds useful...

You're in for a bit of a snipe hunt, unfortunately. Good luck.

 

[TheBSDGuy]

When it comes to NTFS on Macs, all bets are off as far as I'm concerned. I haven't been to this thread in about 2 weeks, so maybe the problem is resolved, but here's what I think you're facing:

Based on the following comment:

So i tried a different usb drive. same thing. the file would play fine on my mac. then i'd copy it over, and it would be corrupt. not all the time. sometmes. i'd copy again sometimes it would be fine sometimes not. mind you not corrupt like the file showing up as 0 bytes like i've seen before, but it would show the full file size as normal. but it just wouldnt play.

That's typical of a bad cable. When a logic board interfaces to a drive, SSD or HD, it basically initiates a handshake sequence saying "I'm about to send you data" and waits for a "go ahead and send it" from the drive. Once the data transfer starts occurring if some of the bits become corrupted because of intermittent data transfers (bad cable) what should be a binary 1 can be a binary zero, and at the point, the file is essentially ruined. About the only type of file that can be recovered from this is non-binary ASCII coded text, where the errors will show up as strange, out of place characters. The drive controller can't "read the mind" of the logic board (CPU) so if it receives bad data, it doesn't know any better, it just writes what it thinks is good data to the drive and then tells the transfer was completed successfully.

The system you have does indeed have a cable as indicated in the following link:

http://www.ifixit.com/Guide/Replacing+MacBook+Pro+13-Inch+Unibody+Mid+2010+Hard+Drive+Cable/4304/1

I assume that's your model.

The other possible problem is NTFS. Mac's weren't designed for NTFS file systems, and considering Microsoft is Apple's arch rival as far as computers are concerned, their support for it hasn't been good. The way the two OSes handle indexing is totally different. All I can offer for you is an opinion, and that is that you need to compare apples with apples, and I would, at least during troubleshooting, limit the new HD to HFS only.

With all that said, the cable problems on some of these units seem to be quite real. I participated in a thread on this site earlier this year on a user that had a system similar, if not identical to yours. In his case, the insulation on the cable had either worn off or it was so bad in the first place that the wires from his cable associated with the optical drive were actually shorting against the case.

I'm guessing it's most likely a cable problem. In any case, good luck.

 

[MacRobert10]

A guy on the Apple site, whose hobby seems to be arguing with everyone else FWIW, states there's "no definitive proof" of significant cable problems on MacBook Pro's and that people shouldn't be assuming things based on the number of web posts about a topic...even though there are probably about a few hundred posts reporting it.

 

[Weaselboy]

A guy on the Apple site, whose hobby seems to be arguing with everyone else FWIW, states there's "no definitive proof" of significant cable problems on MacBook Pro's and that people shouldn't be assuming things based on the number of web posts about a topic...even though there are probably about a few hundred posts reporting it.

People are really funny about their Apple products. We have some forum members here that are the same way... criticize anything Apple does and they act like you just called their children ugly.

There have been quite a few posts in the forums here from users that had symptoms that looked like drive failure and after a new drive did not help a cable replacement fixed the issue. Pretty hard to argue with results.

 

[mirzank]

Thanks for the detailed breakdown. The problem actually hasn't been resolved... I've just been getting more and more frustrated with it.

I THINK its not an NTFS issue because i've been using ntfs drives with macs for years through paragon ntfs. First on a 2007 mac mini with 4 external ntfs formatter drives for media, then a 2010 mac mini, and this current macbook pro. No issues at all. They only started with this optibay drive installation.

I think you're right...it must be a cable issue. From the research I did though the cable problems seem to be with the 2011 macbooks, not my 2010. Now maybe theres na overlap, but i'm not sure.

Do you think maybe my optibay drive caddy might be the one with the problem?

The link you sent me was for the cable for the primary drive my issue is actually with my replacement hard drive drive in an optibay.

this is what i found on ebay: http://www.ebay.com/itm/MacBook-Pro...548?pt=LH_DefaultDomain_0&hash=item27d8be8ab4

I'm going to have to do something about this soon because basically this second drive has been relegated to non-critical functions only now. I have had a corrupt iphoto library recently, and lots of corrupt media files and i'd really like to fix it.

Thanks for taking the time to give me your opinion, i'll look further into what cable suits my macbook and report back.

When it comes to NTFS on Macs, all bets are off as far as I'm concerned. I haven't been to this thread in about 2 weeks, so maybe the problem is resolved, but here's what I think you're facing:

Based on the following comment:



That's typical of a bad cable. When a logic board interfaces to a drive, SSD or HD, it basically initiates a handshake sequence saying "I'm about to send you data" and waits for a "go ahead and send it" from the drive. Once the data transfer starts occurring if some of the bits become corrupted because of intermittent data transfers (bad cable) what should be a binary 1 can be a binary zero, and at the point, the file is essentially ruined. About the only type of file that can be recovered from this is non-binary ASCII coded text, where the errors will show up as strange, out of place characters. The drive controller can't "read the mind" of the logic board (CPU) so if it receives bad data, it doesn't know any better, it just writes what it thinks is good data to the drive and then tells the transfer was completed successfully.

The system you have does indeed have a cable as indicated in the following link:

http://www.ifixit.com/Guide/Replacing+MacBook+Pro+13-Inch+Unibody+Mid+2010+Hard+Drive+Cable/4304/1

I assume that's your model.

The other possible problem is NTFS. Mac's weren't designed for NTFS file systems, and considering Microsoft is Apple's arch rival as far as computers are concerned, their support for it hasn't been good. The way the two OSes handle indexing is totally different. All I can offer for you is an opinion, and that is that you need to compare apples with apples, and I would, at least during troubleshooting, limit the new HD to HFS only.

With all that said, the cable problems on some of these units seem to be quite real. I participated in a thread on this site earlier this year on a user that had a system similar, if not identical to yours. In his case, the insulation on the cable had either worn off or it was so bad in the first place that the wires from his cable associated with the optical drive were actually shorting against the case.

I'm guessing it's most likely a cable problem. In any case, good luck.

----------

People are really funny about their Apple products. We have some forum members here that are the same way... criticize anything Apple does and they act like you just called their children ugly.

There have been quite a few posts in the forums here from users that had symptoms that looked like drive failure and after a new drive did not help a cable replacement fixed the issue. Pretty hard to argue with results.

are we talking about 2010 macbook pros? From my googling around the problem seems to be with the 2011 15 inchers. My problem with with a 13 inch 2010 macbook pro, with a drive in an optibay.

this is the cable i've found on ebay:
http://www.ebay.com/itm/MacBook-Pro...548?pt=LH_DefaultDomain_0&hash=item27d8be8ab4

Is there some way to establish if its maybe my optical bay caddy thats defective? Or is is it really trial and error? New cable. If that doesn't work, then new caddy?

 

[Weaselboy]

are we talking about 2010 macbook pros? From my googling around the problem seems to be with the 2011 15 inchers. My problem with with a 13 inch 2010 macbook pro, with a drive in an optibay.

this is the cable i've found on ebay:
http://www.ebay.com/itm/MacBook-Pro...548?pt=LH_DefaultDomain_0&hash=item27d8be8ab4

Is there some way to establish if its maybe my optical bay caddy thats defective? Or is is it really trial and error? New cable. If that doesn't work, then new caddy?

The drive cable problems have been across all model years. The only way to tell for sure is if you have another machine or external caddy you can swap the drive into to see if it works there, then that cuts the cable out of the picture.