[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: transferring boot



On 7/31/25 14:49, Detlef Vollmann wrote:
On 7/31/25 19:18, Eben King wrote:
I recently got some SSDs, and decided to use one of them (a 256G model) to boot from.  I want the change to be undetectable, in that from a user perspective, nothing seems different, just faster.

I currently have a 2T HD, partitioned with GPT but booting by MBR. Yes, that's probably weird.  When I installed Debian I was unaware that the installer would only install grub to boot using the method that the installer booted.  My BIOS/firmware will boot using either method, but defaults to MBR if both methods work.  You can force it to use UEFI on a one-time basis.  I want the SSD to boot using UEFI.  Is that possible, and if so, what's the best method to go about it?

My ideas are:
1. dd / onto the SSD, then modify it to boot UEFI.  This sounds hard.
2. Install Debian (the same version I run) onto the SSD, then modify
    /etc and whatever else so stuff works.  This sounds error-prone.
3. Wait until I upgrade to Trixie, then let the installer hash it out.


I would go for the first option (dd), then modify grub to boot
from that, then fix the new /etc/fstab to use the correct UUID for /,
and that's it.  Why do you want to switch to UEFI?

It holds no particular advantages right now, but I expect that in the future MBR will be less and less supported. It is starting to look like having the SSD boot UEFI is going to be difficult without a lot of manual work, and I'm mostly OK with that. At some point I'll be pretty much forced to switch, so I'd rather do it on my terms, not those of some random hardware or software.

I'll probably have the SSD boot MBR, then switch when I install Trixie. Upgrading distros is always a giant mess where lots of stuff changes at the same time, so changing the boot method at that time causes little additional pain.


Reply to: