Frankly speaking, you cannot create a
Linux partition larger than 2 TB using the fdisk command. The fdisk
won't create partitions larger than 2 TB. This is fine for desktop and
laptop users, but on server you need a large partition. For example, you
cannot create 3TB or 4TB partition size (RAID based) using the fdisk
command. It will not allow you to create a partition that is greater
than 2TB. In this tutorial, you will learn more about creating Linux
filesystems greater than 2 Terabytes to support enterprise grade
operation under any Linux distribution.
To
solve this problem use GNU parted command with GPT. It supports Intel
EFI/GPT partition tables. Partition Table (GPT) is a standard for the
layout of the partition table on a physical hard disk. It is a part of
the Extensible Firmware Interface (EFI) standard proposed by Intel as a
replacement for the outdated PC BIOS, one of the few remaining relics of
the original IBM PC. EFI uses GPT where BIOS uses a Master Boot Record
(MBR).
(Fig.01:
Diagram illustrating the layout of the GUID Partition Table scheme.
Each logical block (LBA) is 512 bytes in size. LBA addresses that are
negative indicate position from the end of the volume, with −1 being the
last addressable block. Imaged Credit Wikipedia)
Linux GPT Kernel Support
EFI GUID Partition support works on both
32bit and 64bit platforms. You
must include GPT support in kernel
in order to use GPT. If you don't include GPT support in Linux kernelt,
after rebooting the server, the file system will no longer be
mountable or the GPT table will get corrupted. By default Redhat
Enterprise Linux / CentOS comes with GPT kernel support. However, if you
are using Debian or Ubuntu Linux, you need to recompile the kernel. Set
CONFIG_EFI_PARTITION to y to compile this feature.
File Systems
Partition Types
[*] Advanced partition selection
[*] EFI GUID Partition support (NEW)
....
Find Out Current Disk Size
Type the following command:
# fdisk -l /dev/sdb Sample outputs:
Disk /dev/sdb: 3000.6 GB, 3000592982016 bytes
255 heads, 63 sectors/track, 364801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/sdb doesn't contain a valid partition table
Linux Create 3TB partition size
To create a partition start GNU parted as follows:
# parted /dev/sdb Output:
GNU Parted 2.3
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted)
Creates a new GPT disklabel i.e. partition table:
(parted) mklabel gpt
Sample outputs:
Warning: The existing disk label on /dev/sdb will be destroyed and all data on this disk will be lost. Do you want to continue?
Yes/No? yes
(parted)
Next, set the default unit to TB, enter:
(parted) unit TB
To create a 3TB partition size, enter:
(parted) mkpart primary 0 0
OR
(parted) mkpart primary 0.00TB 3.00TB
To print the current partitions, enter:
(parted) print
Sample outputs:
Model: ATA ST33000651AS (scsi)
Disk /dev/sdb: 3.00TB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number Start End Size File system Name Flags
1 0.00TB 3.00TB 3.00TB ext4 primary
Quit and save the changes, enter:
(parted) quit
Sample outputs:
Information: You may need to update /etc/fstab.
Use the mkfs.ext3 or mkfs.ext4 command to format the file system, enter:
# mkfs.ext3 /dev/sdb1 OR
# mkfs.ext4 /dev/sdb1 Sample outputs:
mkfs.ext4 /dev/sdb1
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
183148544 inodes, 732566272 blocks
36628313 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
22357 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 31 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
Type the following commands to mount /dev/sdb1, enter:
# mkdir /data
# mount /dev/sdb1 /data
# df -H Sample outputs:
Filesystem Size Used Avail Use% Mounted on
/dev/sdc1 16G 819M 14G 6% /
tmpfs 1.6G 0 1.6G 0% /lib/init/rw
udev 1.6G 123k 1.6G 1% /dev
tmpfs 1.6G 0 1.6G 0% /dev/shm
/dev/sdb1 3.0T 211M 2.9T 1% /data
