Linux Learning Notes (ii)--host planning and disk partitioning

Recently conducted a systematic study of Linux systems, read the bird's Linux private dishes, excerpts from the study notes are as follows:

1) in a Linux system, each device is treated as a file, and each device will have a device file name.

2) The device file name of the disk is mainly divided into the IDE interface/dev/hd[a-d] and SATA/SCSI/USB interface/dev/sd[a-p] two kinds;

3) The first sector of the entire disk is important because he records important information about the entire disk! The first sector of the disk mainly records two important information, namely:

Main boot Record area (Master boot Record, MBR): Where the boot manager can be installed, there are 446bytes

Split tables (partition Table): Record the state of the entire hard disk partition, with a bytes

4) disk partition tables (partition table)

-The so-called "split" is only for the bytes of the partition table to set it!

--The default partition table of hard disk can only write four groups of segmented information;

These four groups of information are called Main (Primary) or extended (Extended) split slots;

-the smallest unit of the split slot is the magnetic column (cylinder);

--When the system is written to disk, it must refer to the disk partition table to process data for a split slot

5) Extended split/logical split slot

6) Main segmentation, Extended segmentation and logical segmentation

---Primary and extended segmentation can have up to four strokes (hard disk limit)

There can be at most one of the---extension segments (operating system restrictions)

---logic segmentation is a continuous cut-out slot by the extended partition;

---is formatted, as the data access partition slot for the main segmentation and logical segmentation.

---Extended segmentation cannot be formatted;

---the number of logical divisions varies by operating system, in Linux systems, the IDE hard disk has a maximum of 59 logical partitions (numbers 5th to 63rd), and SATA hard drives have 11 logical partitions (5th to 15th).

7) Start-up process

---BIOS: Boot active firmware, will know the first device to boot;

---MBR: The primary boot record block in the first sector of the first bootable device, including a boot management program;

---boot manager (boot loader): a software that can read the core file to execute;

---Core archives: Start the function of the operating system ...

The main tasks of boot loader are the following items:

---provides a menu: Users can choose different boot items, which is an important function of multi-boot!

---into the core archives: Direct point to the program section to start the operating system;

---transfer to other loader: the power-on management function is transferred to other loader.

---each split slot has its own boot sector (bootsector)

The system slots in the---diagram are the first and second split slots,

---the actual boot of the core files are placed in each partition slot!

---loader only know their own system slots in the core files, as well as other loader only;

---Loader can direct or indirectly transfer management to another management process.

---boot loader can be installed in two locations, namely MBR and boot sector.

8) directory tree structure (directory trees)

9) file system relationship to the directory tree (Mount)

The so-called "mount" is the use of a directory as an entry point, the disk partition slot data placed in the directory, that is, access to the directory can read the meaning of the partition slot. This action we call "Mount", the entry point of the directory we call "mount point." Because the root directory is the most important for the entire Linux system, the root directory must be mounted to a partition slot. Other catalogs can be mounted to different slots depending on the user's own needs.

Linux Learning Notes (ii)--host planning and disk partitioning