I have a UEFI system, but I want to install CentOS on a MBR (not GPT) hard disk. The installation program keeps telling me that I must create an "EFI system partition on a GPT disk mounted at /boot/efi". I can't find a way to work around this. Is there a solution? -- Yves Bellefeuille <yan at storm.ca>
On 15 February 2018 at 17:19, Yves Bellefeuille <yan at storm.ca> wrote:> I have a UEFI system, but I want to install CentOS on a MBR (not GPT) > hard disk. > > The installation program keeps telling me that I must create an "EFI > system partition on a GPT disk mounted at /boot/efi". > > I can't find a way to work around this. Is there a solution? >If the installer is doing that then it usually means that the UEFI firmware is either a) not in BIOS compatibility mode b) does not respond in a way that Linux detects or c) the disk is larger than what BIOS compatibility mode will allow. Otherwise anaconda should default to MBR unless it finds the hardware does not know how to deal with MBR. https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/installation_guide/chap-anaconda-boot-options> -- > Yves Bellefeuille > <yan at storm.ca> > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos-- Stephen J Smoogen.
Sometimes in bios it is called legacy mode Sent from my iPhone> On Feb 15, 2018, at 5:31 PM, Stephen John Smoogen <smooge at gmail.com> wrote: > >> On 15 February 2018 at 17:19, Yves Bellefeuille <yan at storm.ca> wrote: >> I have a UEFI system, but I want to install CentOS on a MBR (not GPT) >> hard disk. >> >> The installation program keeps telling me that I must create an "EFI >> system partition on a GPT disk mounted at /boot/efi". >> >> I can't find a way to work around this. Is there a solution? >> > > If the installer is doing that then it usually means that the UEFI > firmware is either > a) not in BIOS compatibility mode > b) does not respond in a way that Linux detects or > c) the disk is larger than what BIOS compatibility mode will allow. > > Otherwise anaconda should default to MBR unless it finds the hardware > does not know how to deal with MBR. > > https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/installation_guide/chap-anaconda-boot-options > > > >> -- >> Yves Bellefeuille >> <yan at storm.ca> >> >> >> _______________________________________________ >> CentOS mailing list >> CentOS at centos.org >> https://lists.centos.org/mailman/listinfo/centos > > > > -- > Stephen J Smoogen. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos
Stephen J Smoogen wrote:> If the installer is doing that then it usually means that the UEFI > firmware is either > a) not in BIOS compatibility mode > b) does not respond in a way that Linux detects or > c) the disk is larger than what BIOS compatibility mode will allow.On the MBR disk, I already have a CentOS 6 partition which works well. I presume that means that there's no problem with the UEFI firmware, no? (The disk has 240 GB; size isn't the problem.) -- Yves Bellefeuille <yan at storm.ca>
On Thu, Feb 15, 2018 at 05:31:42PM -0500, Stephen John Smoogen wrote:> On 15 February 2018 at 17:19, Yves Bellefeuille <yan at storm.ca> wrote: > > I have a UEFI system, but I want to install CentOS on a MBR (not GPT) > > hard disk. > > > > The installation program keeps telling me that I must create an "EFI > > system partition on a GPT disk mounted at /boot/efi". > > > > I can't find a way to work around this. Is there a solution? > > > > If the installer is doing that then it usually means that the UEFI > firmware is either > a) not in BIOS compatibility mode > b) does not respond in a way that Linux detects or > c) the disk is larger than what BIOS compatibility mode will allow. > > Otherwise anaconda should default to MBR unless it finds the hardware > does not know how to deal with MBR. > > https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/installation_guide/chap-anaconda-boot-options >I had the same issue back when I installed 7.x on this box. I couldn't find a way around it, so I finally just went with the flow. I definitely DID have it in legacy mode, or at least the firmware's GUI said I did. -- ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- "And he will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of his government there will be no end. He will reign on David's throne and over his kingdom, establishing and upholding it with justice and righteousness from that time on and forever." ------------------------------- Isaiah 9:7 (niv) ------------------------------
On Thu, Feb 15, 2018, 3:19 PM Yves Bellefeuille <yan at storm.ca> wrote:> I have a UEFI system, but I want to install CentOS on a MBR (not GPT) > hard disk. >Why? While the UEFI spec permits using MBR for booting, it's confusing because there's no actual single standard for MBR. There is for GPT. Anyway, all OS installers I'm aware of on multiple platforms enforce GPT for UEFI installations.> The installation program keeps telling me that I must create an "EFI > system partition on a GPT disk mounted at /boot/efi". > > I can't find a way to work around this. Is there a solution? >Yes, but it means giving bad advice. And that is to enable "legacy" OS support to present a faux BIOS to the booting system instead of exposing UEFI. It's bad advice because you have no good reason for wanting to use MBR, it's an arbitrary request. Chris Murphy