On Wed 13 Apr 2022 at 17:13:39 (-0700), David Christensen wrote: > On 4/13/22 16:07, Peter Hillier-Brook wrote:
> > I've just attempted to Install "Bookworm" to a USB stick and it > > went mostly to plan, apart from the fact that it won't boot. > > However that's not the issue at hand: I can't find a way to > > persuade the installer's partitioner to use GPT instead of the > > MS-DOS partitioning scheme. > > I use the d-i at the simplest level I can (e.g. text "Install" mode > from the main menu). From what I have observed, d-i detects if the > host is using BIOS or UEFI, and chooses MBR or GPT partitioning > accordingly. Assume the host firmware can operate as UEFI, I would use > the CMOS Setup program to set the host firmware to UEFI and then boot > d-i. I didn't know that, probably because I have never tried to run the debian-installer with what's effectively a blank disk.¹ So my answer would be to write a blank partition table onto the USB stick before you start the installer. You can do this with fdisk using its "g" command, or with gdisk using its "o" command. If you want to keep the contents of the stick, rather than starting afresh, you can usually convert it from MBR to GPT with gdisk. If the last partition has been created to completely fill the stick, this will probably fail, because a GPT disk needs room for a backup partition table at the very end. You would need to shrink the last partition's filesystem, and then the partition itself, before converting the stick. ¹ Back in the 1990s, I required dual-booting with DOS6.22, and so I let DOS's FDISK set the disk geometry and create the first partition. Since that era, I've always created my partitioning scheme before starting the installer. Cheers, David.
