GPT

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GPT

"GUID Partition Table (GPT) is a standard for the layout of the partition table on a physical hard disk. Although it forms a part of the Extensible Firmware Interface (EFI) standard (Intel's proposed replacement for the PC BIOS), it is also used on some BIOS systems because of the limitations of MBR partition tables, which use 32 bits for storing logical block addresses and size information. For disks with 512-byte sectors, the MBR partition table entries allow up to a maximum of 2.20 TB (2.20 × 1012 bytes) (the precise value being 4,294,967,295 (232−1) sectors × 512 (29) bytes per sector = 2 TiB−512 bytes = 2,199,023,255,040 bytes).[1] GPT allocates 64 bits for logical block addresses and therefore allows a maximum disk and partition size of 264−1 sectors. For disks with 512-byte sectors, that would be 9.4 ZB (9.4 × 1021 bytes)[1][2] or 8 ZiB−512 bytes (9,444,732,965,739,290,426,880 bytes or 18,446,744,073,709,551,615 (264−1) sectors × 512 (29) bytes per sector). As of 2010, most current operating systems support GPT, although some (including OS X and Microsoft Windows) only support booting to GPT partitions on systems with EFI firmware." [1]

guid-partition-table-schemesvg.png

References:

fdisk limitation

"you cannot create a Linux partition larger than 2 TB using the fdisk command. The fdisk won't create partitions larger than 2 TB."

"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 It is a part of the Extensible Firmware Interface (EFI) standard proposed by Intel as a replacement for the outdated PC BIOS, one of the few remaining relics of the original IBM PC.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)."

Linux Creating a Partition Size Larger Than 2TB - http://www.cyberciti.biz/tips/fdisk-unable-to-create-partition-greater-2tb.html

Linux

yum install parted

parted /dev/sdb
mklabel gpt
# unit TB
# unit GB
mkpart primary 0 0  # should use full disk on newer parted 2.3+ versions
# rm 1
# mkpart primary 0.00TB 3.00TB
# mkpart Ubuntu 0 100G
print
parted -l
quit
.
mkfs.ext3 -L MYEFI /dev/sdb1

FAT32: 

unit MB
print  # get disk max
# mkpart primary fat32 0 32  # this would only be 32MB
# mkpart primary fat32 32 1074   # 1074 comes from 'print' max size
mkpart primary fat32 0 -0  # use whole disk
.
mkfs.vfat -n MYEFI /dev/sdb1  # mkfs.msdos is the same file

List all drive partitions: 

parted -l  # or --list

---

You may get this error when trying to format with VFAT: 

mkfs.vfat: Attempting to create a too large file system

Try formatting with -F 32 

mkfs.vfat -F 32 /dev/sdb1

Also check that your partition is not zero size (can happen if you use mkpart 0 0 on older versions)

---


References:

Microsoft

See Diskpart 

diskpart
list disk
REM  # NOTE: DO NOT SELECT DISK 0 (windows os drive)
select disk 1
clean
convert gpt
create partition primary
REM # Note: or to create an EFI partition:
REM # create partition efi size=112
list part
select partition 1
REM # Note: Label anything you want, but use OEMDRV for RHEL driver disks
format fs=fat32 label="MY_GPT" quick
REM # Note: not required, but you can specify drive letter: "assign letter=s"
assign
exit

References:

keywords

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