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dimme

macrumors 68040
Original poster
Feb 14, 2007
3,021
27,485
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
 

dimme

macrumors 68040
Original poster
Feb 14, 2007
3,021
27,485
SF, CA
I fixed the problem! I used a Gpart Live CD It is a very god and free partition editor.
 

seventyeight

macrumors newbie
Mar 16, 2011
1
0
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?
 

dimme

macrumors 68040
Original poster
Feb 14, 2007
3,021
27,485
SF, CA
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.
 

gmiller1018

macrumors newbie
Dec 14, 2011
2
0
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,
 

gmiller1018

macrumors newbie
Dec 14, 2011
2
0
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. :-(
 
Last edited:
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