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Coffee break- does Time Machine restore disk errors?

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Coffee_manThis is my first coffee break in quite a while and before you chide me it’s a decaf coffee break at the local Starbucks.  It’s good to sit in here for a bit and see what moves me.  Today is going much better than last night as my MobileTechRoundup buds will no doubt attest.  See last night the three of us sat down in our respective time zones to record a new episode of the podcast as we usually do.  All three of us record the podcast on our respective MacBook Pros and usually everything goes hunky dory.  I’m afraid that wasn’t the case last night and my co-hosts are probably not very happy with me right now.  Of course, it’s not my fault.  :)

About halfway through recording our 30 minute show my MBP hung up, Imean it would do some minor things but all running programs were lockedup tight.  I couldn’t even force quit them, they wouldn’t go away.This sad state of affairs left us with a worthless half an episodebecause since the Mac was hung up I couldn’t even recover what hadrecorded to that point.  Talk about a wasted session, sorry guys.

I had to power off to recover and when the MacBook Pro went to restartI got the dreaded "three beeps of RAM death" indication and the bootprocess halted.  This set me back a bit as it’s the same initial errorI got before my hard drive died and was replaced.  This didn’t seemlikely to me since the drive was brand new but there I was.  Alldressed up and nowhere to take a dead Mac.  Ouch.

I finally got the MBP to start up by disconnecting all peripherals andtrying again and again until finally it booted up normally.  Once I hada working system I installed TechTool Deluxe (TTD) that came with theAppleCare extended warranty I had just received that very day.  This isa good diagnostic utility and is the same one used by Genius Paulduring my recent visit to the Apple Store.  TTD had determined backthen that my old drive was failing the tests and Paul had to replacethe drive because TTD couldn’t repair the errors detected, a sure signof a bad drive he told me.  Last night I ran the full suite of testsexpecting the RAM to show errors because that’s what the three beeps atboot time means and it couldn’t be the hard drive again.  To my surprise everything passed the tests withflying colors except the volume structure on the new hard drive.  Itwas flagged with errors and TTD offered to repair them if it could.

I of course told it to feel free to correct the problem although with asinking feeling in my stomach since this was a drive that was justreplaced a week ago.  TTD did its thing for a bit and then informed meit had repaired all of the errors in the volume structure, althoughthese errors could be a sign of bad things to come.  I havesubsequently booted the MBP a few times to see if it would fail andsince the disk repair it has worked fine with no further problems.Granted it’s been less than a day but so far so good so my fingers arecrossed.  This situation has me thinking some scary thoughts about TimeMachine though.  I use it to back up the internal system disk and afterApple replaced my old dead drive they returned the system with justLeopard pre-installed just like a new unit from the factory.  Theinitial boot of the MBP with the new drive gave me the option torestore the Time Machine backup on the external drive used for thebackups and I did that.  I restored everything, settings, users, dataand programs at that time and my MBP came up exactly like it was beforethe drive was replaced.  What I hadn’t counted on was finding similardisk errors on this new drive so soon after having it installed so nowI am wondering- did Time Machine restore everything including the diskerrors?  It doesn’t seem possible but I have to wonder at this point.

22 Responses to “Coffee break- does Time Machine restore disk errors?”

  1. Keaven Normandin Racine

    hey, i know first hand whaet this is… bad ram… bad ram writes bad data.
    it can be easily intermittent, like if a single chip on the stick is causing problem… i seem like a no-body, reviving an old post, but trust me, i make a living on that type of things… save yourself some trouble, replace the ram… you probably already did, since the corruption probably cam back… data corruption can’t cause the 3 beeps, they ARE reliable (one of the only things that still are now-adays) just hoping i can save you another major headache… they replaced your drive for nothing, it was fine, corruption was caused by bad ram… they always overlook the ram…
    run the apple hardware test on your computer if it’s not too late, you’ll get ram errors, i bet you 10$…

    Good luck, take care, have fun, and try to e-mail me what happenned

  2. I have to wonder what is happening here. James I want to be clear that I think that this is in no way your fault.

    Why does your MBP do the three beeps if there is no problem with the ram? Why was it providing this warning code prior to the repair? You were told it was a problem with your harddrive, but this doesn’t explain why you got the ram error beeps (the ram error code and the harddrive are unrelated). Your harddrive has been replaced, but you are once again getting the error beeps and system lockups. Your computer was NOT fixed.

    I am bringing this up because I believe there is a false perception that computers are repaired when we think they are.

    My girlfriend has an ibook that has had intermittent problems like this. The harddrive has been replaced thrice by the “Geniuses” at the San Fran apple store (for the record anyone who is a self-proclaimed genius: clearly is not.) It still shuts itself off at a whim, only to ignore repeated attemps to turn it back on. It also functions like a desktop, in that it cannot run on its battery, and must be plugged in. Any attempt to power on without the powercord plugged in, or to disconnect the cord while in sleep or in full operation is met with a harsh loss of power. At one point it only worked if you pinched the left side of the base of the ibook and tilted the book to a 45 degree angle.

    I’ve found the folks at the genius bar to be lacking somewhat in technical expertise, not as bad as best buy mind you, but if even I can understand that the computer powering itself off is not a harddrive issue (especially after it has been replaced twice previously) shouldn’t the experts know that?

    My theory, which I believe will prove itself to be true (over the next several months) is that James’ MBP problems are endemic to his sepcific unit. Further visits to the genius bar for repairs will result in new components replacing old ones, but the errors he experiences will continue to occur until he has a completely new unit.

  3. My wife has had a similar number of problems with her Mac portable. People also tell her that it must be her fault since things like this don’t happen on Macs.

    Apple also replaced her hard drive. Maybe they are just having supplier problems.

    I also wondered whether there could be problems related to programs running on the Windows side. Could an antivirus program on the Windows side be causing unanticipated problems for the Mac side?

  4. I have to disagree on Time Machine causing this: even if the files were corrupted it is extremely unlikely that Time Machine would reproduce the same problem on the new drive. Firstly, Time Machine would not be able to read corrupted sectors on the old drive just like MacOS wasn’t, so it would either skip them or report the error. Secondly, Time Machine wouldn’t corrupt volume structure as part of the restore process since that data cannot be just restored from the old drive, it’s rebuilt by the MacOS as the files are added so it’s unique to your new drive.

  5. Statistics suck, and people are notoriously bad at reading into them.

    If Apple has a 1% failure rate on MBP hard drives, then out of a million drives, 10,000 will fail. The funny part about that is, it doesn’t matter who gets one of those 10,000. I could get none. Someone else could get one. James could get 10!

    *If* it’s a second failing hard drive, it’s not necessarily James’ fault, unless he’s baking his MBP prior to yanking the hard drive, setting it atop a degausser for a few minutes, and then popping it back into his system.

    Most likely, Time Machine copied some structures improperly, munged some permissions, and now he’s got to play catch up. I’d recommend that James fix permissions on his disk prior to running any more diagnostics.

    (The odd part is, Time Machine doesn’t appear to be block-based. There’s no reason that it should end up writing bad metadata to the volume.)

  6. I agree with Kevin. The issue was probably caused by the files in the backup already being damaged by the dying hard disk and restoring the damaged preferences and settings. If you had just brought back the data files then you may have found some documents that were damaged but not had the OS issues that you experienced.

  7. Your old HDD may have been thrashing files for a while..possibly for a few backups prior to the repair. When you restored from the backup it just copied the bad files and structures over. Hopefully all is well now.

  8. James, if you have an intermittent hardware failure somewhere other than your hard drive (lets say your RAM has a nasty spill every now and then) this could easily lead to a badly corrupted hard drive. If your hardware fails while your drive is being written to this can really mess the drive up, which could explain the second drive with similar problems.

  9. I’m like James, I’m always stick with defective crap, whether or not it’s Apple.

    My Nikon D300 was a lemon, as were my first three iPhones. The over-simple iMovie ’08 even brought my MBP to its knees last week.

    When I got back from CES my HDTV was ruined too…

    Maybe James and I just have bad gadget karma.

  10. >>>has anybody ever considered it might be primarily James & not the hardware/software he uses?

    It is nothing more than Karma. Kendrick torments me. Karma torments him.

    James will just have to start using things that I have no lust interest in.

    Let’s see… vanilla PC running Linux, I think that would be.

    Poor James!

  11. Apple = it just works

    i have never seen such a tech “enthusiast” have so many problems as James. multiple Vista machines all with problems, Mac laptop with problems, iPod Touch with problems, etc.

    yet i use even more machines on a daily basis than you & havent even had a fraction of the problems you have, as i suspect goes the same for many others as well. has anybody ever considered it might be primarily James & not the hardware/software he uses?