To Rescue Nonbooting OS X with Grub?
Question
I had Refind bootloader in Macbook Air 2013-mid. My disk has OSX and broken Ubuntu. Ubuntu messed up my bootloader such that it starts only. I cannot go to grub/refind by pressing ALT, ALT-R, ... My SIP is disabled.
I followed the guides here and here.
I am now in grub>
command prompt where I managed to get by pressing ESC
at startup. In grub
, ls
gives
(proc) (hd0) (hd1) (hd3) (hd1,gpt4) (hd1,gpt2) (hd1,gpt1) error: failure reading sector 0x0 from `hd2'
where
hd1
is my SSD find out byls (hd1)
(hd1,gpt1)
EFI here, fat filesystem, probably swap size 20kB(hd1,gpt2)
75 GB here, probably OS X(hd1,gpt3)
Recovery HD, not sure what(hd1,gpt4)
Ubuntu 16.04, 45 Gb here
So I need to setup a bootloader which has (hd1,gpt2)
and (hd1,gpt4)
in the same table. I may still have refind
but not sure, because Ubuntu probably replaced it.
Problem: ls (hd1,gpt2)/
gives
error: unknown filesystem
I cannot configure the bootloader apparently back with Linux grub. If I could see the contents, I would like to do
set root='(hd1,gpt2)'
...
I really would like to start some live system to fix the thing, but I cannot find any key to boot from USB.
Updates in Linux side
I did many update and upgrade cycles on the Linux side. So the Linux kernel is now 4.4. In startup, I get only Grub menu where is no OS X. Just the Ubuntu and its variations.
So I think the problem is just to link the OS X to Grub but I am not sure about if when I could read OS X filesystem in grub>
.
Unsuccessful attempt of installing refind in Linux
In Linux, install refind
again
sudo apt-add-repository ppa:rodsmith/refind
sudo apt-get update
sudo apt-get install refind
and answer yes
. Restart. However, Grub is still there but not refind.
How can you fix the bootloader in Macbook?
La solution
Just run the refind-install
script with sudo
in the OS X side. I could not get to the recovery mode. This solved the problem.