Bdtyktl

My system currently has this partition setup:

I would like to enlarge /dev/sdb2, the EFI System Partition, to 500MB.

The problem is that I do not want to delete the Windows Recovery Partition (/dev/sdb1) and I do not know how to move the unallocated space after /dev/sdb4 to be adjacent to /dev/sdb2.

Using Linux, I can move the /dev/sdb4 partition to the right by 400MB, but then I cannot move the MSR (/dev/sdb3) as it is of unknown format.

Using Windows, I cannot move the Windows10 partition, and by the way the MSR partition seems hidden so I cannot act on it.

So I'm stuck with only 100MB of EFI partition which is totally insufficient for multiple kernels.

To move sensitive partitions, you need to boot from CD or USB.

Some free partition editors that have boot CD are :

• 
  MiniTool Partition Wizard Free (Bootable CD)


• GParted Live

Of the two, MiniTool has the better user interface.

I suggest before starting, to take an image of the entire hard disk on external
media, using a product that also has a rescue boot CD.
Create this rescue CD and test whether it can see the backup disk and image,
just in case, as any mistake can destroy the disk and render the installed
operating systems unbootable.
My favorite backup product is the free AOMEI Backupper.

Below is the procedure to follow once you boot into the partition editor's boot CD.
It brings the unallocated space to below the EFI (sdb2), but as unallocated space
is not counted as a partition, one needs to rather move its adjoining partition.

1. Move sdb4 right/down by 400MB


2. Do the same for sdb3 (MSR). The unallocated space should now directly follow sdb2.


3. Reboot to test if the disk still functions.
   If reboot is impossible, then the MSR could not be moved - see below.


4. Resize sdb2 to include the unallocated space


5. Reboot

If the tools fail to move the MSR, or if Windows cannot boot after the MSR was moved,
you will need to delete and recreate it.

This is explained in this answer :

Boot into the Windows installation media, and press SHIFT+F10 to open
the command prompt. Type diskpart. Type list disk, and then
select disk X where X is the number of the physical drive
containing the Boot partition. Type list partition to give you the
partition list. I had the EFI System Partition at the start of the
disk now which is 100 MB in size, and the partition list says that it
began at an offset of 1024 kB. Windows considers a megabyte to be 1024
kB so the free space begins at an offset of 1024 + (100*1024) = 103424
kB. Type the command create partition msr size=128 offset=103424. If
you have the sizes and offsets right, this should work, and in my
case, it indeed did.

See also the description of the command Create partition msr.

TLDR: Backup - this is a dangerous process. Then restore the disk, adjusting parititon sizes to taste.

The strategy I would take would be to back up first and adjust partition sizes when I restore. It seems a little odd, but firstly, its idiotproof (if you mess up, you simply restore) and many good backup software gives you the option to resize when you restore, and in many cases would fix the things that would break since its recreating the partitions from scratch.

Doing any sort of file system editing without a backup is irresponsible

My usual backup software's veem endpoint backup and - I've backed up, resized and restored and it seems to work for me -iirc you rightclick on the partition, and set the volume sizes and you're good. This isn't software designed for one off backups, so something else like macrium reflect might work as well.

If you don't want to mess with diskpart, you can do this in GParted. I tested this method on my machine and it works.

1. shrink /dev/sdb4 by 400MB (you've already done this)


2. unmount /dev/sdb2


3. copy /dev/sdb2 into the empty space between /dev/sdb4 and /dev/sdb5 (call this new partition /dev/sdb7)


4. enlarge /dev/sdb7 to take the entire 400 MB


5. delete /dev/sdb2


6. ensure /dev/sdb7 has the esp boot flag


7. if you use linux, update your fstab file to reflect the UUID of the new EFI partition