EFI and MSR partition questions

benedict said:

1. Do only boot drives need EFI and MSR partitions?
2. Do only bitlocker drives need MSR partitions?
3. Can you leave it to diskpart to make sure that the offsets are 4k aligned? I think the default offset is divisible by 1MB.

Microsoft recommendations seem to be all over the place for EFI partition sizes.
This says 256Mb for EFI for 4k AF drives and 16Mb for MSR. Is 100MB or 128MB EFI enough for a dual boot for Windows10 or 11 and linux?

1a. Only boot drives need EFI.

1b. No drives need MSR, although I havke seen claims it is sometimes used for dynamic drives. However dynamic drives are deprecated feature and should no longer be used. It is really personal preference if you keep MSR - even MS are contradictory on this.

2. Bitlocker drives do not use MSR

3. diskpart sorts out boundaries.

4. Standard W10/11 installation uses 260 MB. I would not reduce it but no real need to increase it either.

benedict said:

1. Do only boot drives need EFI and MSR partitions?
According to MS, all GPT drives needs MSR partitions but many systems has none and work the same way.
EFI partitions have the boot managers. They are only needed on boot able drives. 100M Fat32 is the most common.

2. Do only bitlocker drives need MSR partitions?
According to MS, all GPT drives needs MSR partitions.

3. Can you leave it to diskpart to make sure that the offsets are 4k aligned? I think the default offset is divisible by 1MB.
On boot able drives I leave the installation script set the drive. On data drives I leave Disk Manager do it

Microsoft recommendations seem to be all over the place for EFI partition sizes.
This says 256Mb for EFI for 4k AF drives and 16Mb for MSR. Is 100MB or 128MB EFI enough for a dual boot for Windows10 or 11 and linux?
Never seen a EFI partition that use more than 40M. My 100M EFI partition with Win and Linux is only 25M used.

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