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dimme

macrumors 68040
Original poster
Feb 14, 2007
3,447
35,985
SF, CA
I was bored a few weeks ago and installed ubuntu on my mac pro. I forgot it will install grub so it totally messed my OSX boot partition I thought I fixed it buy using rEFIt. Until today when my osx disk would not boot at all. I tried repairing permissions, disk utility , drive genius, rEFIt you name it nothing worked. I had to reformat and reload from my backup. So what is odd now is my windows disk which is in bay 2 shows up in disk utility as the first disk. Do anyone know of a repair tool I can run on my OSX disk.
Terminal gpt -r show -l /dev/disk0 gives me this
gpt show: /dev/disk0: Suspicious MBR at sector 0
start size index contents
0 1 MBR
1 1 Pri GPT header
2 32 Pri GPT table
34 6
40 409600 1 GPT part - "EFI System Partition"
409640 624470624 2 GPT part - "Untitled"
624880264 262151
625142415 32 Sec GPT table
625142447 1 Sec GPT header
And rEFit partition inspector gives me this

*** Report for internal hard disk ***

Current GPT partition table:
# Start LBA End LBA Type
1 40 409639 EFI System (FAT)
2 409640 624880263 Mac OS X HFS+

Current MBR partition table:
# A Start LBA End LBA Type
1 1 409639 ee EFI Protective
2 * 409640 624880263 af Mac OS X HFS+

MBR contents:
Boot Code: Unknown, but bootable

Partition at LBA 40:
Boot Code: None (Non-system disk message)
File System: FAT32
Listed in GPT as partition 1, type EFI System (FAT)

Partition at LBA 409640:
Boot Code: None
File System: HFS Extended (HFS+)
Listed in GPT as partition 2, type Mac OS X HFS+
Listed in MBR as partition 2, type af Mac OS X HFS+, active
 
I fixed the problem! I used a Gpart Live CD It is a very god and free partition editor.
 
I have the same problem here. Do you remember what you did with gParted? Can you give me an detailed explanation what i have to do to repair my MBR?
 
I have the same problem here. Do you remember what you did with gParted? Can you give me an detailed explanation what i have to do to repair my MBR?

I really can't remember what I did to fix it but it was pretty easy. Sorry I can't be of any help.
 
Attempting a recover

My mac is setup for triple boot (OSx, Linux, Windows 7) or at least was till I tried to install Fedora core 16 with grub2. I can still boot OSx but the others are in a non bootable state (I can read the files but I can't get rEFIt to fix the MBR at this point. When I rub te Partition Inspector that is part of rEFIt I get the following:


*** Report for internal hard disk ***

Current GPT partition table:
# Start LBA End LBA Type
2 409640 163725351 Mac OS X HFS+
3 163989504 226902015 Basic Data
4 226904064 312580095 Basic Data
5 163725352 163989503 Linux Swap

Current MBR partition table:
# A Start LBA End LBA Type
1 1 409639 ee EFI Protective
2 409640 163725351 af Mac OS X HFS+
3 * 163989504 226902015 83 Linux
4 226904064 312580095 07 NTFS/HPFS

MBR contents:
Boot Code: Unknown, but bootable

Partition at LBA 409640:
Boot Code: None
File System: HFS Extended (HFS+)
Listed in GPT as partition 1, type Mac OS X HFS+
Listed in MBR as partition 2, type af Mac OS X HFS+

Partition at LBA 163989504:
Boot Code: GRUB
File System: ext3
Listed in GPT as partition 2, type Basic Data
Listed in MBR as partition 3, type 83 Linux, active

Partition at LBA 226904064:
Boot Code: Windows BOOTMGR (Vista)
File System: NTFS
Listed in GPT as partition 3, type Basic Data
Listed in MBR as partition 4, type 07 NTFS/HPFS

Partition at LBA 163725352:
Boot Code: None
File System: Unknown
Listed in GPT as partition 4, type Linux Swap

Any suggestion for what I can do to fix this, I got into this problem by using a linux partition editor to try to fix an original issue with the failure of grub2 to install and now have this mess. Any help would be appreciated,
 
I have noticed that the MBR table has an EFI protected section that I DO NOT have in the GPT table so I am assuming that is the real issue. The MBR has the same number of partitions but it INVENTS an EFI protected partition so I have to assume I need to get one on the GPT side to get the "generated" MBR to be correct. This I am unsure how to do since I guess I don't know what purpose it serves. :-(
 
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