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.
(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/sdbSample 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/sdbOutput:
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 primaryQuit 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/sdb1OR
# mkfs.ext4 /dev/sdb1Sample 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 -HSample 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
