Into the world of the little-known hard disk partition table

What is the hard disk partition table? It can be said to support the hard disk to work properly. When people use a computer, sometimes due to abnormal operations, sometimes due to virus attacks, a certain partition will disappear or the hard disk will not start. The reason is that the hard disk partition table is damaged. Many people are unfamiliar with this. For this reason, today Xiaobian leads everyone into the world of hard disk partition table to understand its related knowledge.

● Basic knowledge about sector number:

Introduce three confusing terms for the hard disk sector numbering rule "physical sector number", "absolute sector number" and "logical sector number".

We all know that there are two ways to locate the hard disk sector:

1. Directly locate the combination of cylinder, head, and sector 3 (obtained by this numbering method) The sector number is called the physical sector number);

2. Position by sector number (also divided into "absolute sector number" and "logical sector number". Conversion relation

these two approaches is positioned below the number shown in FIG :( disposed FIG sectors per track are the hard disk 63)

provided for each channel shown in FIG hard disk sector All are 63

As shown in the figure, since most of the hard disks currently use a kind of “vertical partition structure”, the left picture shows a hard disk with 2 heads and 1 disk number. There are two ways to represent the sector of the 0-head, that is, 0 cylinder 0 head 1 sector = absolute 0 sector, and 1 head is also represented by 2 types, namely: 1 cylinder 0 head 1 sector = absolute 63 sectors. If the number of heads is 4 and the number of discs is 2 as shown in the figure on the right, the absolute sector number of the figure is carried along the direction of the arrow line perpendicular to the disc.

Above, we said the physical sector, the absolute sector numbering method, and the logical sector number is the sector numbering method adopted by the operating system, and the operating system can only read the data content inside the partition. Therefore, the logical sector is numbered starting from the first sector in each partition. As we will explain in the following mbr: the hard disk track of the sector where mbr is located does not belong to the partition, and then it is behind It is the content of the partition, so in general it is absolutely 63 sectors = c: partition logic 1 sector.

Ok, let's list a table to summarize the differences between the three numbering methods:
3 kinds of numbering methods

It should be noted that this article assumes that each sector of the hard disk used is The number is 63. The number of sectors per hard disk that you use on your hand can be found in the settings of the hard disk parameters in the BIOS settings. Previous12Next page Total 2 pages