On Thu, Apr 7, 2022 at 5:21 PM Neal Gompa <ngompa13@xxxxxxxxx> wrote: > > On Thu, Apr 7, 2022 at 7:10 PM Demi Marie Obenour <demiobenour@xxxxxxxxx> wrote: > > Can the disk be partitioned so that it is valid for *both* MBR and GPT? > > > > There are two options here: protective MBR and hybrid MBR. > > Protective MBRs are well-supported and I believe created by default > when you create a GPT partitioning scheme for BIOS systems already > with Anaconda. I think it's done with UEFI as well, but if not, we can > certainly force it. > > The second option is known as hybrid MBR. The gdisk utility can create > them: https://www.rodsbooks.com/gdisk/hybrid.html > > Needless to say, it's... interesting... I'm not sure if more tools > support hybrid MBRs since this was last refreshed in 2019. > > It's also kinda scary and not really necessary unless you need to > interoperate with OSes that expect MBR in a mixed BIOS+UEFI boot > setup. Strictly speaking per the UEFI spec, hybrid MBR's don't exist. Creating such a thing means it's really MBR and the GPT is invalid, and it requires all software to treat it as such. The only valid MBR with a valid GPT, is a protective MBR (PMBR) which is defined as having one partition the size of the device or the maximum size supported by MBR if the device is bigger. -- Chris Murphy _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
