corpnewt / MountEFI

An even more robust edition of my previous MountEFI scripts

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Unable to mount EFI on High Sierra. #2

Closed wpoosanguansit closed 4 years ago

wpoosanguansit commented 4 years ago

Hi,

I have found your script from one of the videos I watched on youtube. I tried to run the script and it works on internal drives. However, when I try to mount EFI on the USB drive, it just doesn't show anything or display any error. Is there a way that I can debug the issue what is going on and to correct it? Thanks for your help.

corpnewt commented 4 years ago

How did you create the USB drive? If you used my gibMacOS script and didn't explicitly choose GPT - it's MBR, and that won't have an EFI partition.

-CorpNewt

wpoosanguansit commented 4 years ago

Thanks for suck a quick response. I did use this command to create the bootable drive:

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/Install\ macOS\ Catalina/

How do I specify GPT in this case? Or is it relevant at all? Thanks for your help.

corpnewt commented 4 years ago

Can you show me the output of diskutil list in the terminal? That command doesn't change the partition scheme, it only formats the target volume, so if the disk was already MBR, it would remain MBR.

wpoosanguansit commented 4 years ago

/dev/disk7 (internal, physical):

: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *31.0 GB disk7 1: Apple_HFS Install macOS Catalina 31.0 GB disk7s1

corpnewt commented 4 years ago

FDisk_partition_scheme

Yep - it's MBR - so there is no EFI to mount.

-CorpNewt

wpoosanguansit commented 4 years ago

Let me check out your gibMacOS script then. Thanks.

corpnewt commented 4 years ago

You could still use createinstallmedia as you did this time - you'll just want to format the entire disk with a GUID Partition Table first.

-CorpNewt

wpoosanguansit commented 4 years ago

Thanks. Let me check out how I do set the GUID Partion Table.

corpnewt commented 4 years ago

You could either use Disk Utility and erase the entire device (you'll likely need to check View -> Show All Devices to see it) - or you can do it in the terminal with the following command:

diskutil partitionDisk /dev/disk# GPT JHFS+ "USB" 100%

Replacing /dev/disk# with your disk number (disk7 in your pasted output from diskutil list).

-CorpNewt

wpoosanguansit commented 4 years ago

Thanks. That works! I am creating the installer now. Thanks again.

On May 2, 2020, at 12:29 PM, CorpNewt notifications@github.com wrote:

diskutil partitionDisk /dev/disk# GPT JHFS+ "USB" 100%

corpnewt commented 4 years ago

Not a problem!

-CorpNewt