On Tuesday, 22 December 2020 15:32:27 GMT Rich Freeman wrote: > On Tue, Dec 22, 2020 at 7:58 AM Peter Humphrey <pe...@prh.myzen.co.uk> wrote: > > Just a quickie - is there a way to enable a machine built on an MSDOS BIOS > > to recognise a partition on a 4TB external disk? I think I know the > > answer already, but just in case... > > I suspect most newer firmwares are fine with it (even in legacy mode), > and ancient ones would need a firmware update, so good luck with that.
As I expected... > You might be able to mitigate the issue with a boot partition close to > the start of the disk. I'm honestly not sure if that works with > something like a USB hard drive. I'm not sure how old this system is > either. I wondered about that. I'm nervous, though, because this is my ultimate backup disk, and of course I don't want to endanger it. This disk is an external USB unit, not for booting from. Mr Google tells me the model was releases in 2007. I will have bought it within a year or so of that. > Back in the day MBR patches for large disks were a pretty common > thing. I'm not sure how much any modern OS depends on the firmware to > do disk IO once it is booted, and I'm not sure that most bootloaders > even need help from the firmware beyond maybe whatever goes in the > boot sector. This is why some GRUB modes require a secondary > partition near the start of the disk to handle certain > filesystems/etc. (Or at least used to - GRUB and EFI have gotten so > good that I don't pay much attention to that stuff on newer hardware > and with common filesystems, even including ZFS.) Thanks for the extra detail, Rich. -- Regards, Peter.