Hello, I thought I'd post a new thread on this issue. My goals is to have a single default partition scheme on a sata disk that allows me to use either Bios(mbr) or EFI(gpt) systems on these drives. Also the goal is to keep the partition scheme unchanged (boot;root;swap;'usr/local') but be able to set up different file systems and distributed file systems on these drives to facilitate testing a wide variety of cluster architectures. I'd sure appreciate some 'thinking outside the box' ideas for these mostly 2T sata drives. I intend to only use one bootloader (grub legacy) but that is not a fixed limitation. /usr/local will be the only storage if one of these drives is used for secondary or additional capacity, thus preserving the partition scheme.
Here is the essences of what Neil posted before:: You can use gdisk and a GPT whetheryou are using BIO or EFI. The difference is in your first partition. For EFI it must be type EF00 and formatted with FAT. For BIOS booting you need to start the disk with a small BIOS compatibility partition of type EF02. This is 1M here and you don't format or use it, it just has to be there. And. I'm not sure it can be done. BIOS needs an EF00 partition at the start. EFI calls for an EF00 partition, which is recommended at the start but I don't think it's compulsory that it is there. I have heard of people using sda2 as the ESP where sda1 is a Windows rescue partition. So you may get away with p1 EF02 partition p2 EF00 partition, formatted as FAT and mounted at /boot root and swap partitions as you see fit. You could try it and see, but I'm not sure it could be guaranteed to work on all EFI hardware, although it should work on all BIOS hardware........ I'd use gdisk to set the partition type to get the partition table listing to include :: (EF02, EF00)? This doc seems to suggest there is a way to configure such disks [1], as do other docs I have read, but do not give explicit examples just how to do this. So is at [1]: https://wiki.manjaro.org/index.php?title=Some_basics_of_MBR_ v/s_GPT_and_BIOS_v/s_UEFI Now, I should use GPT (gdisk) and label and setup the disk complete with a gpt labeled table, but preserve the MBR for legacy booting of most bios based systems? If that is correct, then here is what the partition scheme could look like, for a 2T drive:: Number Start (sector) End (sector) Size Code Name 1 2048 411647 200.0 MiB EFO2 FAT 2 411648 270747647 128.9 GiB 8200 Linux swap 3 270747648 1859022847 757.3 GiB 8300 Linux filesystem 4 1859022848 3907022847 976.6 GiB 8300 Linux filesystem Maybe someone can edit this table and show me an example (no worries on boundaries or sizes) and include a few sentences to explain and guide me on this effort? curiously, James
