RHEL: GPT/MBR partition tables (using disks larger than 2 TiB)

# Tested on RHEL 6 & 7

# Up to now the default type of the partition table of a hard disk is MBR (msdos).
This
# old method presents some problems like the limitation of having a maximum of four primary
# partitions but the main problem is that we can't go beyond the first 2 TiB of the disk.

# Nowadays physical disks are growing in size quickly. A way of solving this problem is
# by switching to GPT (GUID Partition Table) partitioning scheme.

# To partition a disk using GPT we first have to write a GPT label to it. The way to do
# it is the following:

parted /dev/<sde> mklabel gpt
   Warning: The existing disk label on /dev/sde will be destroyed and all data on this disk will be
   lost. Do you want to continue?
   Yes/No? Yes
   Information: You may need to update /etc/fstab.


# If we want to make the disk usable by LVM, first we have to partition the disk and mark
#
the new partitions with the "LVM label" so let's create
a new partition and change
# its name and flags

parted /dev/sde
   GNU Parted 3.1
   Using /dev/sde
   Welcome to GNU Parted! Type 'help' to view a list of commands.
   (parted) mkpart primary 1M 500M
   (parted) name 1 mypart
   (parted) p
   Model: ATA VBOX HARDDISK (scsi)
   Disk /dev/sde: 4295MB
   Sector size (logical/physical): 512B/512B
   Partition Table: gpt
   Disk Flags:

   Number  Start   End    Size   File system  Name    Flags
    1      1049kB  500MB  499MB               mypart

   (parted) set 1 lvm on
   (parted) p
   Model: ATA VBOX HARDDISK (scsi)
   Disk /dev/sde: 4295MB
   Sector size (logical/physical): 512B/512B
   Partition Table: gpt
   Disk Flags:

   Number  Start   End    Size   File system  Name    Flags
    1      1049kB  500MB  499MB               mypart  lvm

   (parted) q
   Information: You may need to update /etc/fstab.


# On RHEL 6, 'fdisk' is not able to manage disk partition table anymore:

myrhel6:/root#> fdisk -l /dev/sde
   WARNING: GPT (GUID Partition Table) detected on '/dev/sde'! The util fdisk doesn't support GPT. Use GNU Parted.
   [...]

# On RHEL 7, we get a message indicating that 'fdisk' support is in experimental phase:

myrhel7:/root#> fdisk -l /dev/sde
   WARNING: fdisk GPT support is currently new, and therefore in an experimental phase. Use at your own discretion.
   [...]


# To switch back to MBR partition table, do the the following:

parted /dev/<sde> mklabel msdos
   Warning: The existing disk label on /dev/sde will be destroyed and all data on this disk will be
   lost. Do you want to continue?
   Yes/No? Yes

0 (0)
Article Rating (No Votes)
Rate this article
Attachments
There are no attachments for this article.
Comments
There are no comments for this article. Be the first to post a comment.
Full Name
Email Address
Security Code Security Code
Related Articles RSS Feed
LVM: Move allocated PE between Physical Volumes
Viewed 747 times since Sat, Jun 2, 2018
RHEL: Handling SCSI disks
Viewed 1025 times since Sun, May 27, 2018
ZFS: Snapshots and clones on zfs filesystems
Viewed 727 times since Sun, Jun 3, 2018
chrt command: Set / Manipulate Real Time Attributes of a Linux Process
Viewed 310 times since Mon, Feb 17, 2020
Linux - How to get IP and MAC address of ethernet adapter in Linux
Viewed 489 times since Fri, Jun 8, 2018
What is OS Watcher Utility and How to use it for Database Troubleshooting ?
Viewed 2779 times since Thu, Jun 21, 2018
debian How to check Debian CVE status using python script
Viewed 471 times since Sun, Sep 23, 2018
Linux Chage Command to Set Password Aging for User
Viewed 445 times since Tue, Sep 11, 2018
Oracle Linux 7 – How to audit changes to a trusted file such as /etc/passwd or /etc/shadow
Viewed 1067 times since Wed, Jul 25, 2018
How to run command or code in parallel in bash shell under Linux or Unix
Viewed 530 times since Tue, Aug 6, 2019