I'm trying to erase my hard drive by reformatting. I am following the steps here:


I am using the Opt ⌥ Cmd ⌘ R option on startup to install the latest OS compatible with my device. When I get to the erase screen, I see the following hard drive items listed:

enter image description here

This is different than what the directions are showing. Should I be erasing both "Macintosh HD" and "disk1"? I've never made any changes to my hard drive, it's a MacBook Pro 2014. Not sure why there are two entries there.

  • Booted to Internet Recovery Mode with opt-cmd-R you won't get the latest but the original system your Mac was delivered with (or at least 10.6.8? or 10.7 if you have an older Mac)! If macOS Sierra 10.2.4 is already installed this may be different - check footnote 2! – klanomath Jul 3 '17 at 19:30

'disk1' is a temporary structure & the 'disk' you are currently booted from, generated by the image you downloaded from Apple as part of Internet Recovery.
It will disappear as soon as you boot regularly from your HD.

That's how you are able to format your main 'Macintosh HD' drive, which you cannot do from the drive you are booted from.

You can verify this since the system won’t let you erase disk1 even if you attempt that operation - that’s a snake eating its own tail situation.

  • Ok so I should just erase "Macintosh HD", and can ignore "disk1" ? – user243948 Jul 3 '17 at 18:44
  • Yes, though it wouldn't let you format that disk anyway [or shouldn't]. – Tetsujin Jul 3 '17 at 18:50

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