3 Replies Latest reply: Sep 19, 2012 4:08 PM by John Galt
daveungar Level 1 (0 points)

This computer is a non-retina mid-2012 MacBook Pro.


Using DiskUtil in Terminal shows the correct disk configuration:


   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:  GUID_partition_scheme                        *750.2 GB   disk0

   1:                               EFI                         209.7 MB   disk0s1

   2:            Apple_HFS Macintosh HD            749.3 GB   disk0s2

   3:            Apple_Boot Recovery HD             650.0 MB   disk0s3


However, booting up with Cmd-R just goes to the Internet Recovery, and booting up with Option Key shows 2 identical Macintosh HD icons - selecting either one boots the system regularly from the Macintosh HD; no Recovery Partition shows up.  I had two eligible computers and the first one was updated directly from the App Store; this one was done with a bootable USB drive.


35 years into the "microcomputer revolution" I really hope that someone can suggest a solution other than "reinstall the operating system."  Not that I don't appreciate help, but this should be fixable with a less drastic solution. The parition is there, something needs to be told to recognize it.  Also, I don't know that reinstalling will produce any different results, although reinstalling directly from the App Store might "turn on" whatever is "turned off."


Thank you.

MacBook Pro, OS X Mountain Lion (10.8.1)
  • John Galt Level 8 (44,675 points)

    This is completely normal. By booting OS X Recovery you are accessing the Recovery partition.


    The Recovery partition is normally hidden, since it is intended to be for "emergency use only". As a longtime computer user, this may understandably annoy you, but there really is nothing you ought to do with it.


    Reinstalling the OS won't help since it will just recreate the recovery partion, even if you reformat or completely replace the drive.


    You may see suggestions from users from time to time to reinstall OS X. This scatter-shot approach is almost never justified on a Mac, since most problems are due to conflicting or poorly written third party software unrelated to the OS, and a reinstallation won't help.


    Replacing a failed hard disk is one valid reason to reinstall OS X. It's difficult to come up with any others.


    See the diskutil manpages to determine how to mount the recovery partition so that you may examine its contents (which are read-only). You'll then be able to get yourself into all sorts of trouble.


    This excerpt from the Lion Ars Technica review may save you the time:


    Doing so reveals the partition as a normal HFS+ volume. The top level contains a directory named com.apple.recovery.boot which in turn contains a few small files related to booting along with an invisible 430MB internally compressed disk image file named BaseSystem.dmg. Mount that disk image and you find a 1.52GB bootable Mac OS X volume containing Safari, most of the contents of the standard /Applications/Utilities folder (Disk Utility, Startup Disk, Terminal, etc.), plus a Mac OS X Lion installer application. In other words, it looks a lot like a standard Mac OS X installer DVD.


    That was the idea - to eliminate the need for a system recovery DVD.


    As you can see the recovery partition probably won't have much to interest you anyway.


    To get a better impression of how all this works (N.B. the following is NOT for the faint-hearted):


    1. Clone your system to an external volume
    2. Boot from the external volume
    3. Completely erase your internal HD, removing all existing partitions
    4. Unplug your external volume and boot OS X Recovery
    5. Reinstall OS X



  • daveungar Level 1 (0 points)

    Thanks for the comments, John.  I probably should have been more specific in my title to my post.  I can't get the Recovery Partiition to work, although it's there.  Holding Cmd-R at boot-up doesn't start it, and booting with the Option key shows two hard disk icons but they are both named Macintosh HD and both boot up the regular system (even though there is actually only one Macintosh HD partition.  So I can only recover from an OS failure with my USB installer or with Apple's Internet installer.   Since I'm using a portable computer  (MacBook Pro) it would be nice to know that if I were traveling somehwere and had a OS problem or disk repair problem that I could use the Recovery Partition to fix it.


    This problem may take care of itself because the 10.8.2 release is out.  I'll see if applying the update fixes this and post the result.


    Thanks again.

  • John Galt Level 8 (44,675 points)

    Thanks for the clarification - but I thought you could boot OS X Recovery successfully?


    Holding ⌘ R at startup should result in OS X Recovery, which looks like this:



    If you see that, it's normal. Is that what you're seeing?


    On the other hand holding an Option key at startup invokes Startup Manager, which looks like this:




    ... except that one of the volumes shown should be named "Recovery HD" or "Recovery-10.8.x" depending on whether you are running Lion or Mountain Lion, respectively.


    If you select the "Recovery" volume that should bring you to OS X Recovery as in the first screenshot.


    Please confirm that instead of this, you are seeing two apparently identical volumes, both named "Macintosh HD", no "Recovery" volume appears at all, and selecting either one results in a normal boot.


    If that is the case something is amiss and I have no idea what could have caused it.


    I do not believe updating to 10.8.2 will fix it but update OS X anyway. OS X 10.8.2 is an overall improvement.


    If this bothers you then I think the only way to properly create a correctly named and functional "Recovery" partition that appears as a selection in Startup Manager would be to follow the "not for faint-hearted" steps I presented earlier. It's up to you to determine if this problem is significant enough to warrant the procedure.


    Should you decide to do that, I would not proceed without having a reliable and tested backup plan, which to me would mean no fewer than two backups - preferably one clone, plus one Time Machine backup.


    If you are still covered under AppleCare you could impose upon Apple to fix this, but be aware in that case they will probably just do the same thing - which means don't even think about approaching the Genius Bar without having already backed up your MacBook.