1 2 3 Previous Next 33 Replies Latest reply: Apr 25, 2012 7:25 AM by Pondini Go to original post
  • 15. Re: avoid Timemachine falling back to internal hdd
    Linc Davis Level 10 Level 10 (118,495 points)

    FYI, the OP's problem was probably caused by the file tmbootpicker.efi, which is at the root level of any TM volume in Lion. That's what he needed to delete.

  • 16. Re: avoid Timemachine falling back to internal hdd
    sadrian-dev Level 1 Level 1 (0 points)

    "Die Axt im Haus..."

    Manchmal zählt eben doch nur das Resultat.

     

    Grüss mir Hamburg - die Axt, die mir einst eine süsse Kerbe ins Herz geschlagen hat...

     

    Sebastian

  • 17. Re: avoid Timemachine falling back to internal hdd
    sadrian-dev Level 1 Level 1 (0 points)

    You're kidding .. .right?

     

    Last thing I did before the recovery was taking a look at the hidden files on the SSD but I had no clue that this was the answer. -.-

     

    Can you give further explanation of this files' use?

  • 18. Re: avoid Timemachine falling back to internal hdd
    sadrian-dev Level 1 Level 1 (0 points)

    I forgot to mention: Still no gremlins. Nowhere.

  • 19. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    Linc Davis wrote:

     

    FYI, the OP's problem was probably caused by the file tmbootpicker.efi, which is at the root level of any TM volume in Lion. That's what he needed to delete.

    The problem occurred only when the TM volume was disconnected and Time Machine wanted to run a backup. 

     

    How could that cause Time Machine to change the destination to the internal HD?

     

    I was under the impression that file came into play only via Startup Manager, to allow booting from the copy of the Recovery HD on the TM volume. 

     

    Is there some documentation anywhere?

  • 20. Re: avoid Timemachine falling back to internal hdd
    Linc Davis Level 10 Level 10 (118,495 points)

    Is there some documentation anywhere?

     

    None that I know of, but I've noticed that the file is always present on TM volumes and is new in Lion. I think the presence of that file identifies the volume to backupd as a destination. I don't know specifically why TM was defaulting to the boot drive, but I don't see any other plausible explanation in this thread. One would have to do some experiments to try to reproduce the behavior.

  • 21. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    It's only present on local (not network) TM volumes, and only since 10.7.2, when TM started copying the Recovery HD (if present) from theOSX volume being backed-up.

     

    And since the volume in question wasn't even connected when Time Machine was trying to do a backup, it seems rather unlikely that it would affect Time Machine for just that user.  I've not been able to reproduce the behavior, and have seen only one other thread with a similar (but not identical) problem.

  • 22. Re: avoid Timemachine falling back to internal hdd
    Linc Davis Level 10 Level 10 (118,495 points)

    The volume in question is the boot volume, which was being defaulted to as a backup destination. What I'm suggesting is that there's causal relationship between that issue and the fact that an EFI file, which is normally present at the root level of a TM volume, but not of a boot volume, was present on this particular boot volume. If this issue ever comes up again, I'd try deleting that EFI file, as well as the backups folder, from the boot volume and see whether TM still recognizes the volume as a destination. I strongly suspect that it won't.

  • 23. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    Linc Davis wrote:

     

    The volume in question is the boot volume, which was being defaulted to as a backup destination. What I'm suggesting is that there's causal relationship between that issue and the fact that an EFI file, which is normally present at the root level of a TM volume, but not of a boot volume, was present on this particular boot volume.

    We have no idea whether there was a copy of that file on the OSX volume.  

     

    And it seems pretty clear that the EFI file has to do with starting from the Recovery HD on the TM volume (especially since it isn't actually a separate partition, but is hidden in the Backups.backupdb folder).

     

    If this issue ever comes up again, I'd try deleting that EFI file, as well as the backups folder, from the boot volume and see whether TM still recognizes the volume as a destination.

    That's not what Time Machine uses to determine the destination for the backups - - it uses the entry in the preferences file. 

     

    I've had multiple backup volumes connected; when one was ejected, Time Machine just waited patiently for it to be reconnected, rather than try to use a different one. 

     

    What I find suspicious is the change in the entry in the prefs file:  on Snow Leopard and Leopard, it's DestinationUUID (singular); on Lion, it's DestinationVolumeUUIDs (plural).  When that was noticed in testing, speculation was that Apple was responding to the many requests for dual backups, or backups in two places (such as home and work) with automatic switching.  Since there's nothing in the GUI (or tmutil) about it, nothing has come of that yet. 

     

    To see if something like that had somehow been triggered, I did try manually copying another UUID there (once my OSX volume, once another TM volume with backups), then ejecting the TM volume named in the prefs, but nothing changed.  When the next backup was due, TM just went into Delayed as usual.

     

    And deleting the prefs file didn't change anything for the user in this thread (or the other one).

  • 24. Re: avoid Timemachine falling back to internal hdd
    Giangiva Level 1 Level 1 (0 points)

    Hello everybody,

     

    sorry to revive this old post, but it is the one I found most similar to the problem I'm facing.

     

    Actually, when I disconnect the USB Time Machine drive, TM falls back to the internal hard drive (Macintosh HD).

    The next time a backup should occur, then, it says "the disk identity is changed".

    As soon as I reconnect the backup drive, everything goes back to normal by itself.

    I tried reading the prefs (defaults read /Library/Preferences/com.apple.TimeMachine) when the drive is connected AND when the drive is disconnected: they are the same! Nothing changes!

    Nevertheless, time machine tries to backup to the boot drive whenever the usb drive is not there.

    I don't have any backups.backupdb in the boot drive.

    I have a mac book pro which came with Lion preinstalled.

    When I'm at office, I switch the time machine preference's file with another one, so time machine backups on the net, but while I'm travelling I backup on the external usb drive.

    I tried to reset the file with no luck.

    My boot drive is encrypted with file vault 2, the usb backup drive is encrypted as well (I created the crypted partition within disk util).

     

    Anybody has any hint on how to solve this issue?

     

    Thanks!

  • 25. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    Giangiva wrote:

    . . .

    I tried to reset the file with no luck.

    It's not clear what you mean by that; if you didn't, try a "full reset" per #A4 in Time Machine - Troubleshooting.

     

    Otherwise, there haven't been any more posts to either thread with this situation;  all I can suggest is, perhaps something in you installation of OSX is damaged.  Try installing a fresh copy, per Installing the ''combo'' update and/or Reinstalling OSX.

  • 26. Re: avoid Timemachine falling back to internal hdd
    Giangiva Level 1 Level 1 (0 points)

    Sorry for my bad phrasing, I did already the "full reset" as per your troubleshooting #A4.

     

    I'll try to reapply the combo update.

     

    For the time being, reinstalling osx looks too much work for me. If I don't find any other fix, I'll try to find some time to do it.

     

    What looks strange to me, is that the TM preferences don't change when I unplug/replug my usb drive, so for what reason TM tries to backup on a different drive?

     

    Do you think there are other preference files which might affect this behaviour?

     

    I tried to look for something like this myself but I had no luck.

     

    Thank you!

  • 27. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    Giangiva wrote:

     

    Sorry for my bad phrasing, I did already the "full reset" as per your troubleshooting #A4.

    Ah, that's what I thought, but wanted to be sure.

     

    I'll try to reapply the combo update.

    Worth a try.

     

    For the time being, reinstalling osx looks too much work for me. If I don't find any other fix, I'll try to find some time to do it.

    It's not hard, but can take a while if you have to download OSX again. 

     

    What looks strange to me, is that the TM preferences don't change when I unplug/replug my usb drive, so

    The Preferences shouldn't change -- the USB drive is still your designated backup drive.

     

    for what reason TM tries to backup on a different drive?


    I have no idea.  As far as I can tell, you're the 3rd person to have it do that.  Neither of the other two have posted back (5 months later), so we don't know if they fixed it or not.  I even tried to force it by manually adding entries to the prefs file, but they were ignored. 

     

     

    Do you think there are other preference files which might affect this behaviour?

    No.  It's all controlled by the TM prefs file.

  • 28. Re: avoid Timemachine falling back to internal hdd
    Giangiva Level 1 Level 1 (0 points)

    I just reapplied the latest two updates (the giant combo one and the later light one) but it didn't help.

     

    Could this problem be related to the fact that both the source drive/partition (Macintosh HD) and the destination drive/partition (I called it BackupUSB) are encrypted?

     

    Did you ever try this kind of combination?

     

    Thanks a lot for your support!

  • 29. Re: avoid Timemachine falling back to internal hdd
    Pondini Level 8 Level 8 (38,720 points)

    Giangiva wrote:

     

    I just reapplied the latest two updates (the giant combo one and the later light one) but it didn't help.

    Rats. 

     

     

    Could this problem be related to the fact that both the source drive/partition (Macintosh HD) and the destination drive/partition (I called it BackupUSB) are encrypted?

    It certainly shouldn't, and the two other folks didn't mention encryption.

     

    Did you ever try this kind of combination?

    No.  I've experimented with encrypted backups, but not an OSX volume.   Lots of folks have, though, without this problem.

     

    I'd forgotten that, as unlikely as it seems, one of the other users found that doing a full restore fixed it.  See sadrian-dev's post (the 6th blue one) in this thread:

     

    "I wiped the SSD and did a full recovery from my TM backup. Voilà! Everything works just as it should! Perfect."