Linux disk partition MBR GPT

Disk: The actual data is composed of many platters, robotic arms, heads and spindle motors, and the reading and writing is performed mainly by means of a mechanical arm which allows the head to be read and written on the platter (under the rotation of the spindle motor, the disc follows the rotation). Because the volume of data written on a single disk is limited, multiple platters exist.

Speed of the disk:

5400 Turn/s

7200 Turn/S

The faster the speed, the longer the head across the unit time, the more data written, the same, the calorific value is higher.

sector, track, cylinder

The head on the platter is a track, and a plurality of discs in the vertical direction form the cylinder.

The minimum unit of disk is the sector, with each sector size of 512bytes.

The disk is represented in the Linux system

All Linux devices are abstracted into a file that is stored in the/dev directory;

Device name is generally hd[a-z] or sd[a-z]

The IDE device name is HD[A-Z],SATA,USB,SCSI and the name of the device is sd[a-z]

Partitioning

Divides a disk logic into partitions, each of which is used as a standalone disk for easy administration.

Different partitions by: device name + partition number means, such as Sda1\sda2

The mainstream partitioning mechanism is divided into MBR and GPT two kinds.

partitioning is not a physical, but a logical concept.

The MBR (Master Boot Record) is a traditional partitioning mechanism that is applied to the vast majority of PC devices that use the BIOS.

Apple PC EFI partition mechanism.

MBR supports 32bit and 64bit systems

MBR supports limited number of partitions

MBR only supports hard drives up to 2T, more than 2T drives will only use 2T space

MBR occupies a total of 512bytes of the first sector of the disk,

The first 446bytes is the system boot code section

The next 4 16bytes is a partitioned table

The remaining 2bytes is the boot ID, 55 and AA can not be modified, if there is a change, it will not boot the system boot

Primary Partition

Only four primary partitions can be created at a maximum

Extended Partition

An extended partition occupies a primary partition location, and the extended partition is not available, it is just a virtual

Logical Partitioning

Created based on an extended partition, it is physical and can be used. Linux supports a maximum of 63 IDE partitions and 15 SCSI partitions

GPT (GUID Partition Table), solves many drawbacks of MBR

Support for more than 2T disks

Backward compatible MBR

Must be available on UEFI-enabled hardware

Must use 64bit system

Mac\linux\windows 7 64bit can support GPT partition format

Both UEFI and BIOS are motherboard systems

Linux disk partition MBR GPT