Delete EFI Partition

Question

I run diskutil list and have this schema:

/dev/disk1
#:                       TYPE NAME                    SIZE       IDENTIFIER
0:      GUID_partition_scheme                        *1.0 TB     disk1
1:                        EFI EFI                     209.7 MB   disk1s1
2:                  Apple_HFS Mac HDD                 999.9 GB   disk1s2

I want to delete all information about EFI partition (EFI bootloader) and use instead legacy boot with Chameleon. (is already installed but BIOS run EFI bootloader in first time ever, don't cant change this).

How I can do this whithout break all my hard disk?

Answer 1

It's unclear precisely what your problem is -- you've said what you want to do, but not why you want to do it. AFAIK, Chameleon should work just fine with an EFI System Partition (ESP). My suspicion is that whatever problem you're encountering is actually an issue with the firmware; some EFIs (including Apple's) have problems booting in BIOS mode (which Chameleon uses) if the disk uses the GUID Partition Table (GPT), or require that the protective MBR in the GPT have certain features. Apple's firmware, for instance, requires that the GPT have a hybrid MBR, and that one of the partitions in the hybrid MBR have its boot flag set. Thus, if you're using Apple hardware, you might try creating a hybrid MBR and setting the boot flag on one of your partitions. My GPT fdisk (gdisk) software can do this. Check the Chameleon documentation to see if it uses the MBR's boot flag for anything; if so, you might need to be careful about which MBR partition gets that flag.

If you're using a Hackintosh configuration, it gets trickier, since the details vary from one firmware implementation to another. I'm also not sure if this site permits discussion of Hackintosh setups. If that's what you've got, you might be better off asking on a Hackintosh site.