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I used Option+Command+P+R to try and fix a sleep issue in OSX. From there I'm a little confused about what happened but I ended up in a mac recovery mode (offering to reinstall OSX), which I tried to exit out of as quickly as possible.

When it rebooted, it seems to be jumping straight to grub, which needs telling which partition to boot and I can't boot OSX (only Ubuntu).

It's as though I've changed the active partition (is that even relevant for EFI?). Can this be fixed from inside ubuntu? I have a retina display macbook, so no CD, and I'd like to fix this from inside Ubuntu ideally.

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  • I should say that each time I end up at "grub rescue>". – Dan Seddon Feb 17 '14 at 22:27
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Try booting with a CD-R or USB flash drive image of rEFInd. This should enable you to boot into OS X and re-install rEFInd there (or just re-run the relevant bless command from the rEFInd OS X installation instructions -- see step #8).

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  • Thanks Rod - does this imply that rEFInd has been broken and that I need to fix it? I'm unclear on what has broken exactly. Thanks for your fast responses! – Dan Seddon Feb 18 '14 at 5:12
  • My suspicion is that your firmware's boot option has been changed from rEFInd to GRUB. Under EFI (even Apple's weird EFI), you can install as many boot loaders/managers as you like, but of course the firmware will try to execute just one of them first. This value can be changed via OS X's bless utility or in various other ways, and my suspicion is that this has accidentally happened and needs to be undone. rEFInd on a USB flash drive is just a handy emergency tool. Re-installing rEFInd or using bless manually should fix the problem permanently (or until it recurs). – Rod Smith Feb 18 '14 at 18:04
  • Following step #8: sudo bless --setBoot --folder /efi/refind --file /efi/refind/refind_x64.efi reinstated my rEFInd boot menu, thanks! – Dan Seddon Feb 19 '14 at 4:02
  • I used mcnesium's solution for getting back in however, which doesn't require a CD. – Dan Seddon Feb 19 '14 at 4:05
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Press Option during startup. This starts in Startup Manager, where you can select an OS X volume or other volumes to start from.

There are a number of other key combinations that may help you to get back to the original boot menu.

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  • While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. – Olli Feb 17 '14 at 22:56
  • sorry, answer edited. – mcnesium Feb 18 '14 at 8:36
  • Holding "Option" down gave me a list of EFI options, getting me back to my original and letting me back in to OSX to follow Rod's instructions above, thanks! – Dan Seddon Feb 19 '14 at 4:03

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