FreeBSD 9.0 - GPT boot problems?

Scot Hetzel swhetzel at
Sat Aug 4 19:12:36 UTC 2012

On Sat, Aug 4, 2012 at 9:23 AM, Torfinn Ingolfsen
<torfinn.ingolfsen at> wrote:
>> The gpart bootcode command is quite apart from and unrelated to (as far as I can tell) the EFI partition.
> Yes, this is what I have found out too.
>> I think the EFI partition is supposed to be the first partition on a GPT-partitioned disk.
> This is not required by the specification as far as I can tell, but there are writings on the net saying that some implementations
> requires this (MS Win7 for example).

Microsoft wants the GPT Disks partitions layouted as:

  Extensible Firmware Interface System Partition (ESP) ~100MB

  OEM Partition (optional)

  Microsoft Reserved Partition (MSR) [Drive <16GB - MSR = 32MB, Drive
>= 16GB - MSR = 128MB]
  - used to reserve space that is later broken in to smaller partition
for use by meta data (i.e. dynamic disks)

  Data Partitions (FAT, NTFS, ...)

If these partitions (ESP, OEM and MSR) were mixed in with the Data
Partions, then you would be unable to grow the filesystems.


More information about the freebsd-stable mailing list