Unable to find ESP install

[Neurobomber]

I got a weird one here, maybe someone can help…

First I tried installing rEFInd from just the basic install script but the rEFInd startup never came up. Then I tried doing it manually but then again no such luck. So I tried installing it in /Volumes/ESP manually and that STILL didn't work! After that I removed everything in /Volumes/ESP and /EFI

Okay, then I tried running the script again with the --esp tag and it worked! I was able to see the boatloader screen and the install Ubuntu icons from my flash drive.

Unfortunately there was no option to boot Mac. Even when I installed Ubuntu, I didn't see that icon either. I now have to hold the option key if I want to boot mac.

Here's the weird part: I can't find the location of the rEFInd install! It's not in /Volumes/ESP nor /EFI and yes I even checked for hidden folders. I tried going through the script but I couldn't find an alternate location it could install to. If I could find them I could either remove them so I won't have to hold the option key to boot up or I could edit the config files to get the boot loader icons to show up.

Anyway, has anybody else encountered this and have a solution?

MacBook Pro
13-inch, Early 2011
Processor 2.7 GHz Intel Core i7
Memory 8 GB 1333 MHz DDR3
Graphics Intel HD Graphics 3000 512 MB
Software OS X 10.8.5 (12F45)

[joevt]

Enable the Disk Utility debug menu.
http://macs.about.com/od/usingyourmac/qt/Enable-Disk-Utilitys-Debug-Menu.htm

Start Disk Utility and enable "Show every partition" from the debug menu.

Now you can use Disk Utility to see and mount EFI partitions. Mount an EFI partition and search for rEFInd.

Make sure you have "scan_delay 1" in the rEFInd.conf file.

[Roderick W. Smith]

I've never used Joe's method, but it would probably work. You can manually mount partitions with the mount command, or filesystem-specific variants like mount_msdos, as in:

mkdir /Volumes/esp
sudo mount -t msdos /dev/disk0s1 /Volumes/esp

This should mount your ESP at Volumes/esp.

Setting scan_delay 1, as Joe suggests, is likely to overcome the problem of rEFInd not detecting OS X; that can happen sometimes when launching a boot loader on a volume other than the one on which rEFInd is installed.

[Wolfgang Smetanig]

Hello,

have the same problem as the starter of the topic.

After entering:
sudo mount -t msdos /dev/disk0s1 /Volumes/esp

I´ve got:
mount_msdos: Unsupported sector size (0)

Any helps for this?

Thanks in advance

[Roderick W. Smith]

Wolfgang, it's possible that your ESP isn't /dev/disk0s1; or maybe your disk uses 4096-byte sectors, and OS X's FAT driver can't cope with that. To start, I recommend you examine your partition table(s) to figure out where your ESP really is.

[bagus tris]

Same problem with same MBP (13inch, i7, 2012). I have checked my ESP partition, and it shows true to be /dev/disk0s1. Here the output of gdisk,
Command (? for help): i
Partition number (1-7): 1
Partition GUID code: C12A7328-F81F-11D2-BA4B-00A0C93EC93B (EFI System)
Partition unique GUID: D9DA4F13-66C6-42E0-BA2B-5B8ACC1DF068
First sector: 40 (at 20.0 KiB)
Last sector: 409639 (at 200.0 MiB)
Partition size: 409600 sectors (200.0 MiB)
Attribute flags: 0000000000000000
Partition name: 'EFI System Partition'

the output of diskutil list is,
dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *750.2 GB disk0
1: EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 169.3 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
4: Apple_HFS Recovery HD 650.0 MB disk0s4
5: 0FC63DAF-8483-4772-8E79-3D69D8477DE4 126.3 GB disk0s5
6: Linux Swap 6.3 GB disk0s6
7: 0FC63DAF-8483-4772-8E79-3D69D8477DE4 446.7 GB disk0s7

and the output of mount -t msdos /dev/disk0s1 /Volume/esp is the same,
mount_msdos: Unsupported sector size (0)

Previously, I install refit, and after yosemite upgrade it failed to show boot option. Then, I tried to install refind, and the problem appears as shown above.

[Roderick W. Smith]

bagus tris, my first guess is that your ESP is damaged. You might be able to repair this with the fsck_msods utility in OS X, as in sudo fsck_msdos /dev/disk0s1. I can't promise this will work, though, and in fact it could even make matters worse. If you can mount the ESP in Linux, I recommend you back it up from there before you try fsck_msdos on it. (Also, In Linux, the equivalent to fsck_msdos is dosfsck. You could try that if fsck_msdos doesn't help.)

In a worst-case scenario, if you can back up the files on the ESP, you could create a fresh filesystem on it (using newfs_msdos in OS X or mkdosfs in Linux) and copy the original files back.