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3.5.2. Disk Drives with MBR on UEFI Systems

Systems with UEFI firmware require a disk with a GUID Partition Table (GPT). When installing Red Hat Enterprise Linux on a disk with a Master Boot Record (MBR; sometimes also called msdos) label, the disk must be relabeled. This means you can not reuse existing partitions on a MBR-partitioned disk, and all data on the disk will be lost. Make sure to back up all data on the drive before installing Red Hat Enterprise Linux.
A GUID Partition Table is only required on the system's boot drive - the disk where the boot loader is installed. Other drives can be labeled with a Master Boot Record and their partition layout can be reused.
There are several ways to install Red Hat Enterprise Linux on an UEFI system and use a drive which has a Master Boot Record. You can:
  • Attach the drive to an existing Linux system and use an utility such as parted or fdisk to create a GPT label on the drive. For example, to create a GPT label on disk /dev/sdc using parted, use the following command:
    # parted /dev/sdc mklabel gpt


    Make sure you specify the correct drive. Relabeling a disk will destroy all data on it, and parted will not ask you for a confirmation.
  • Perform an automated Kickstart installation, and use the clearpart and zerombr commands. If your system uses UEFI firmware, using these commands on the boot drive will relabel it with a GPT.
  • During a manual installation in the graphical user interface, when you get to the partitioning screen. Select an option other than custom partitioning (for example Use All Space). Make sure to check the Review and modify partitioning layout check box, and click Next.
    On the following screen, modify the automatically created layout so it suits your needs. After you finish and click Next, Anaconda will use your layout and relabel the drive automatically.