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5 Replies Latest reply: Apr 14, 2013 7:18 PM by Dude! RSS

where to install boot loader with OL 6.2 with Win7 GPT partition style

asmirnov Newbie
Currently Being Moderated
Hi,
With double boot systems I always install GRUB in the MBR.
Now this time I am on Win7 64 bit and using GPT.
Since my partition style is no longer MBR but GPT which option should I choose above?
Would it work if I select to install boot loader into MBR?
Thank you
Anatoliy
  • 1. Re: where to install boot loader with OL 6.2 with Win7 GPT partition style
    Dude! Guru
    Currently Being Moderated
    GPT is a disk partition format that requries UEFI (EFI) firmware. MBR requires a standard PC-BIOS. The PC-BIOS (32/16-bit) cannot read a GPT (64-bit) partition, nor can the UEFI firmware use MBR and the two are incompatible. Some PC systems provide classic BIOS and UEFI support and you will have to decide when you setup the system. You cannot convert your primary hard drive between GPT and MBR without completely erasing it.

    Special hybrid bootloaders exist for UEFI systems to support MBR, such as rEFit (free) or EasyBCD. In your case it might be easier to install Oracle Linux 6 under GPT and UEFI firmware. UEFI based systems have an EFI System Partition (/boot/EFI), where each OS installs their own loader. The EFI boot manager loads and runs the Linux GRUB boot loader as an EFI application.

    I have not tried it, but the Anaconda installer should detect a GPT partition and allow you to install the GRUB bootloader into /boot/EFI. According to the OL 6 installation guide, if your 64-bit x86 system uses UEFI you will need to manually create a /boot ext3 partition.

    Btw, any reason why you choose 6.2 and not 6.4?
  • 2. Re: where to install boot loader with OL 6.2 with Win7 GPT partition style
    asmirnov Newbie
    Currently Being Moderated
    Dude,

    Thank much for the quick response.

    My PC is Win7, I beleive it does support EFI because it's first partition of size 96M is "EFI System partition" as Disk manager says.
    The other partition is a primary (NTFS) with GPT partition style (this is where I have Win7), the free space will have Linux.

    I tried 6.4. The install went to the point where partitioning layout was written to disk but right after that I got this error

    Unable to read package metadata. This may be due to a missing repodata directory.
    Please unsure that your install tree has been correctly generated.
    Cannot retrieve repository metadata (repomd.xml) for repository: anaconda-UEK2.
    Please verify its path and try again.

    I saw this error here in the forum

    Oracle Linux 6 u3 Installation via FTP

    (with regard to 6.3), the discussion was around a different kernel used in 6.4. It was said I need to have HTTP or FTP install. It was said 6.2 was the last kernel that doesn't require that if I am not mistaking. So I thought I will take a step back and try 6.2 at leat to make sure it does work. It did, the only glitch I made I forgot to select 'customize partition layout' option so the install wrote everything to the disk and didn't ask me about the boot loader where to install. Linux was installed fine but I list Win7, not I reinstalled Win7 and want to try Linux one more time, but I am was not sure about the boot record(loader) where to. So according to what you said

    "UEFI based systems have an EFI System Partition (/boot/EFI), where each OS installs their own loader."

    yes I can this partition in Win7 as I mentioned above, so should I then select 'first sector of the boot partition?

    Thank you
    Anatoliy

    forgot to mention - my BIOS does support UEFI, 'UEFI/Legacy Boot' option is set to Both

    Edited by: asmirnov on Apr 13, 2013 9:04 PM
  • 3. Re: where to install boot loader with OL 6.2 with Win7 GPT partition style
    Dude! Guru
    Currently Being Moderated
    (with regard to 6.3), the discussion was around a different kernel used in 6.4. It was said I need to have HTTP or FTP install. It was said 6.2 was the last kernel that doesn't require that if I am not mistaking.
    Sorry I think this is nonsense. Where did you read that?

    It rather sounds like you used the 6.4 "boot" DVD which is simply wrong for what you are going to do. The boot DVD is for local network installs or troubleshooting your system. It does not contain any software repository. Just get the standard 6.4 distribution DVD (V37084-01), which contains the installation software and is also bootable.

    First sector of the boot partition or sector 0 usually means the Master Boot Record (MBR), which stores and loads either the bootloader or OS image. If your disk is GPT, MBR is meaningless. MBR is only used if you use Legacy Boot (PC-BIOS). UEFI BIOS boots to GPT. The UEFI BIOS emulates a PC BIOS for compatiblity with 32-bit applications.

    UEFI/Legacy boot "both" means that your computer can fallback to Legacy BIOS if it cannot boot using UEFI, depending on your disk partition schema and data. Do you also have a UEFI/Legacy priority setting? But nevertheless, UEFI cannot boot any OS under MBR, and legacy BIOS cannot boot a OS that was installed under GPT. The partition schema of your disk is either GPT or MBR, but not both.

    For reference, the following seems to apply:
    http://forums.lenovo.com/t5/tkb/articleprintpage/tkb-id/Special_Interest_General@tkb/article-id/22

    I suggest to check your windows installation to verify it is GPT or MBR. If you set the system to "UEFI only" does it still boot? Did you check the Oracle Linux/RHEL 6 installation guide for installing under UEFI?

    If I were you, I'd rather upgrade the system to 8 GB of RAM and install VirtualBox as previously discussed and forget about all of this.

    Edited by: Dude on Apr 14, 2013 1:13 AM
  • 4. Re: where to install boot loader with OL 6.2 with Win7 GPT partition style
    asmirnov Newbie
    Currently Being Moderated
    Dude wrote:
    (with regard to 6.3), the discussion was around a different kernel used in 6.4. It was said I need to have HTTP or FTP install. It was said 6.2 was the last kernel that doesn't require that if I am not mistaking.
    Sorry I think this is nonsense. Where did you read that?
    My fault I think
    It rather sounds like you used the 6.4 "boot" DVD which is simply wrong for what you are going to do. The boot DVD is for local network installs or troubleshooting your system. It does not contain any software repository. Just get the standard 6.4 distribution DVD (V37084-01), which contains the installation software and is also bootable.
    Yes you are correct, the 3.5G file for some reason didn't work for me as bootable, now it does, I did burn it in Win7 now instead of XP
    I suggest to check your windows installation to verify it is GPT or MBR. If you set the system to "UEFI only" does it still boot? Did you check the Oracle Linux/RHEL 6 installation guide for installing under UEFI?
    Yes it does boot
    If I were you, I'd rather upgrade the system to 8 GB of RAM and install VirtualBox as previously discussed and forget about all of this.
    This will be a downgrade for me from 16G :)

    I did install 6.4 now, the Linux is fine, Windows though fails with GRUB2 with

    invalid efi file path

    The grub.conf entry for Win7 is

    rootnoverify (hd0,2)
    chainloader +1

    I am going to check on this, thank you for your quick response.

    Regards
  • 5. Re: where to install boot loader with OL 6.2 with Win7 GPT partition style
    Dude! Guru
    Currently Being Moderated
    This will be a downgrade for me from 16G
    Even less reasons not to use VirtualBox. Re: Oracle Linux distro to support GPT out of the box Anyway, I'm done suggesting VirtualBox.
    I did install 6.4 now, the Linux is fine, Windows though fails with GRUB2 with invalid efi file path.
    Oracle Linux or any other RHEL derivative does not use GRUB 2. The current version is 0.97. GRUB 2 is used in Ubuntu, Fedora and other desktop Linux distributions. Again, the EFI boot manager loads and runs the Linux GRUB boot loader as an EFI application. As far as I'm aware, you can not use GRUB of RHEL or Oracle Linux the other way around to load UEFI Windows.
    Yes it does boot
    That means your primary hard disk is using a GPT partitioning style and you cannot use MBR style for dual boot, unless you install a very special EFI boot manager as I previously tried to explain. If dual boot is what you want than you need to either erase your computer and install Windows 7 using MBR, or install Oracle Linux 6 using UEFI as explained in the installation documentation.

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