To mount an EFI boot partition, follow these steps:
1. Discover the volume identifier for your EFI boot partition.
Run this command:
diskutil list
The output should look something like this:
/dev/disk0 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *251.0 GB disk0 1: EFI 209.7 MB disk0s1 2: Apple_HFS Macintosh HD 250.1 GB disk0s2 3: Apple_Boot Recovery HD 650.0 MB disk0s3
In this case, the volume identifier of the EFI partition is disk0s1
2. Create a mount point.
A mount point is a directory where a non-booted volume is mounted. On Mac OS X, mount points are typically created in /Volumes. We can create a directory called efi within /Volumes by running the following command:
mkdir /Volumes/efi
3. Mount the EFI partition at the efi mount point.
Run the command:
sudo mount -t msdos /dev/disk0s1 /Volumes/efi
That’s it. Your EFI volume will be mounted. Modify it at your own risk.