Separating EFI partitions of Ubuntu 20.04 and Mac OSX on Macbook Pro
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28-05-2021 - |
Pergunta
I installed Ubuntu 20.04 alongside OSX on my early 2015 Macbook pro by following this answer. And somehow I messed up.
I created a separate 400MB EFI partition for Ubuntu but, the system automatically selected Mac OS EFI partition. Can I transfer the Ubuntu boot files to the separate Partition without reinstall? I recently started using Linux. please someone help me out?
$: fdisk /dev/sda
Disk /dev/sda: 233.78 GiB, 251000193024 bytes, 490234752 sectors
Disk model: APPLE SSD SM0256
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: E25C4B1F-9E64-4BCB-B346-07F1727F45F3
Device Start End Sectors Size Type
/dev/sda1 40 409639 409600 200M EFI System
/dev/sda2 409640 234784639 234375000 111.8G unknown
/dev/sda3 234784768 235567103 782336 382M EFI System
/dev/sda4 235567104 362520575 126953472 60.5G Linux filesystem
/dev/sda5 362520576 391817215 29296640 14G Linux swap
/dev/sda6 391817216 392595455 778240 380M Microsoft basic data
/dev/sda7 392597504 490233855 97636352 46.6G Microsoft basic data
$ gdisk /dev/sda
Disk /dev/sda: 490234752 sectors, 233.8 GiB
Model: APPLE SSD SM0256
Sector size (logical/physical): 512/4096 bytes
Disk identifier (GUID): E25C4B1F-9E64-4BCB-B346-07F1727F45F3
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 490234718
Partitions will be aligned on 8-sector boundaries
Total free space is 3045 sectors (1.5 MiB)
Number Start (sector) End (sector) Size Code Name
1 40 409639 200.0 MiB EF00
2 409640 234784639 111.8 GiB AF0A
3 234784768 235567103 382.0 MiB EF00
4 235567104 362520575 60.5 GiB 8300
5 362520576 391817215 14.0 GiB 8200
6 391817216 392595455 380.0 MiB 0700
7 392597504 490233855 46.6 GiB 0700
Solução
I am not sure why the Ubuntu installer allows the user to select which EFI partition to use, then ignores the setting and installs to the first EFI partition. Below are the step to move the boot files to the second EFI partition.
Boot to Ubuntu.
Press the control+option+T key combination to open a Terminal window.
Enter the command below to become the root user.
sudo bash
Enter the command below to format the second EFI partition.
Note: This command will erase the contents of this partition.
mkfs.vfat -F 32 -n EFI2 /dev/sda3
Enter the command below to mount the second EFI partition.
mkdir efi2 mount -t vfat /dev/sda3 efi2
Enter the commands below to copy the boot files from the first EFI partition to the second EFI partition.
mkdir efi2/EFI mv /boot/efi/EFI/BOOT efi2/EFI mv /boot/efi/EFI/ubuntu efi2/EFI
Enter the commands below to get the UUID of the two EFI partitions.
blkid /dev/sda1 blkid /dev/sda3
Edit the
/etc/fstab
file to change the UUID value for the mount point/boot/efi
. This can be accomplished by replacing the UUID of the first EFI partition with the UUID of the second EFI partition. Below is the command to open the file in thenano
editor.nano /etc/fstab
Enter the command given below to output the contents of the
/etc/fstab
file. Visually confirm the changes to the file.cat /etc/fstab
Enter the command given below to unmount the second EFI partition.
umount efi2 rmdir efi2
Enter the commands given below to close the Terminal window.
exit exit
Restart the Mac.