UEFI partition format

Technical issues/questions of an intermediate or advanced nature.
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Ed_P
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UEFI partition format

Post#1 by Ed_P » 18 Sep 2019, 15:03

I seem to recall reading that the UEFI partition doesn't have to be FAT to work. Was that posted here someplace? :%)
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tagon
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UEFI partition format

Post#2 by tagon » 13 Nov 2019, 10:04

From Wikipedia:
The EFI system partition needs to be formatted with a file system whose specification is based on the FAT file system and maintained as part of the UEFI specification; therefore, the file system specification is independent from the original FAT specification.[2][3] The globally unique identifier (GUID) for the EFI system partition in the GUID Partition Table (GPT) scheme is C12A7328-F81F-11D2-BA4B-00A0C93EC93B, while its ID in the master boot record (MBR) partition-table scheme is 0xEF. Both GPT- and MBR-partitioned disks can contain an EFI system partition, as UEFI firmware is required to support both partitioning schemes. Also, El Torito bootable format for CD-ROMs and DVDs is supported.
So it has to be an EFI system partition, which is not FAT, but derived from FAT. :-)

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UEFI partition format

Post#3 by Ed_P » 13 Nov 2019, 16:44

Thanks tagon. But somewhere someone wrote that the standard isn't enforced or something and the EFI partition can be NTFS or other format. I think they even said they had done it and it worked. Unfortunately I don't remember who or where and I apparently didn't bookmark the site. :(
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M. Eerie
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UEFI partition format

Post#4 by M. Eerie » 17 Nov 2019, 11:50

Ed_P wrote:
13 Nov 2019, 16:44
and the EFI partition can be NTFS
Have a look here

And here

:)

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UEFI partition format

Post#5 by Ed_P » 17 Nov 2019, 14:31

:good: Thank you M. Eerie. :beer:
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rych
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UEFI partition format

Post#6 by rych » 26 Nov 2019, 13:21

By the way, what's the minimum size for the first FAT32 partition for the porteus EFI? 100MB, 200, 300, 350MB?

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UEFI partition format

Post#7 by Ed_P » 26 Nov 2019, 16:08

50MB should work but most use 100MB.

My Porteus EFI USB drive is just 1 partition and Porteus runs fine on FAT32.
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