Partitions uses in default Mac OS installation? I plan to install Linux on my Macbook Pro and before removing an important partition, I'd like to know what I need to keep in order to be able to do a recovery to MacOS in case I need to.

For information, here's what I currently have on my macbook :


EFI : 200Mo
Apple Core storage : 465.1Go
Apple Recovery : 619.9Mo


Here's the fdisk output : (sorry, in French)



I believe I can remove the "Apple Core Storage", but can I also remove the EFI or no?

The idea is to be able to launch a Apple Recovery in case I need it and get back my computer like it was when I bought it.

Thank you for your help.
You need to keep the EFI partition in order to be able to boot OSX. You could, however, install an alternative boot loader, such as "rEFInd".

You do not need to keep the "Apple Recovery" partition, but you should, because if you mess up the normal Mac partition so that you cannot boot from it any more, you might still be able to boot into the Recovery partition and fix the OSX system from it.

You could also copy both the EFI and Recovery partitions to a new disk, e.g. to an external disk, and then boot from it. If that works, then you'd be safer playing with the partitions on your main drive, seeing what works, and still be able to boot from the external disk, because the Mac's boot ROM will search every connected internal and external disk for an EFI partition in order to see if it can boot from it.

To test this, hold down the Option (alt) key when the Mac starts up - then you will get a list of bootable partitions.

For installing Linux, I suggest you do these steps:


Get a large enough external disk and make a backup of each of your partitions, using a block copy method, or by using OS X's Disk Utility, with the "New disk image from ..." command from the File menu. You could also try my tool "iBored" for this.
Boot OSX and open Disk Utility. Select the disk, then "Partitions". Select the large OSX partition and click the [+] button to add a new partition. Make it large enough for your Linux system. This will then make the OSX partition smaller if there's enough free space on it. Now you have a new free partition to install Linux on.
See if you can install rEFInd and see if that supports booting into Linux (it should, but I have not tried it myself).
If something goes wrong, you can always restore from your external backup.