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. 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. 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.) Rich -- Rich
