Initializing a disk from with GPT

Mayu Inc. pomomayu at
Sun Jan 29 09:39:09 PST 2023

Thank you Sir.

Yes sorry the remaining installation steps were omitted to keep it concise.
We want to use PFSs so we opted for the manual installation.

A few things on the 'gpt init' method:

When using the -B flag the machine freezes:

# gpt init -f -B -E da0 // Machine freezes

Also since the 'gpt init' method creates a boot partition on the 's0'
partition, do we install the boot code during installation as shown:

# cpdup /boot /dev/da0s0a

Does this require a separate disklabel for the s0 partition that 'gpt init'

# disklabel -B -r -w da0s0
# disklabel -e da0s0
  a:    0    1g    msdos

Would the 's1' slice only contain partitions 'b' and 'd', requiring another

# disklabel64 -B -r -w da0s1
# disklabel64 -e da0s1
  b: 32g * swap
  d: *  * HAMMER2

Entire sequence (assuming machine doesn't freeze):

 # gpt destroy da0
 # gpt init -f -B -E da0
 # gpt show da0

# disklabel -B -r -w da0s0
# disklabel -e da0s0
  a:    0    1g    msdos

# disklabel64 -B -r -w da0s1
# disklabel64 -e da0s1
  b: 32g    *     swap
  d: *        *     HAMMER2

# newfs_hammer2 /dev/da0s1d

Proceed with installation.

On Sun, Jan 29, 2023 at 5:12 AM Matthew Dillon <dillon at> wrote:

> Most modern BIOSes boot EFI by default, so all you should need to do to
> get past the BIOS (but not actually boot dragonfly yet), is:
> gpt init -f -B da0
> That will create an EFI bootable drive, which is to say it creates the EFI
> slice table, puts a msdos filesystem in slice 0 along with the appropriate
> EFI boot file, and puts a DragonFly disklabel on slice 1 which you can then
> edit.  That would get past the BIOS, but not be able to boot DragonFly
> without a few more steps since no filesystems have been created on da0s1a
> (/boot) and da0sd (which is typically the root, / ), and no base system has
> been installed on them, along with the appropriate /boot/loader.conf,
> /etc/fstab, and so forth on the target drive.
> It is usually easier to boot an install image from usb and have the
> installer setup the drive for you.
> -Matt
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