Linux boot process
Skill administrator (2000-12-23 09:07) 〖Back〗 〖Forward〗
Starting the Linux system, usually requires LILO (The Linux Loader), which can also guide Linux, but also boot other operating systems, including MS-DOS or WIN 9X, and Windows NT. When LINUX is installed, the LILO can be mounted in the MBR of the hard disk or in the boot sector of the active partition. When the microcomputer starts, the BIOS loads the MBR, then starts from the current active partition, after LILO gains the control of the boot process, the LILO prompt is displayed, as shown below: LILO Boot: This time if the user does not do anything, Lilo will wait Formation time (for example, 5 seconds) automatically guides the default operating system, and if you press the Tab button during this time, you can see a list of bootable operating systems, such as LILO boot: [Tab] Win98 Linux boot: above Indicates that LILO can boot both Win98 and Linux operating systems, and Win98 is the default operating system. If the user typed Linux after the LILO prompt, the user can start the Linux operating system. Another feature of Linux is that many parameters can be passed to the Linux kernel, such as: boot: Linux Sigle specifies that Linux enters single user mode. When the user selects the launching the Linux operating system, LILO reads the Linux image from the partition where the ROOT file system is located according to the pre-set information, and then loads the kernel image and handles the control to the Linux kernel. After the Linux kernel gets control, continue booting the system with the following steps: 1. The Linux kernel is generally compressed, so it first decompressed itself. Some of the code in front of the kernel image completes decompression. 2. If the system is installed in the system, Linux can identify the SVGA card, Linux prompts the user to select the appropriate text display mode. However, if text mode is set in advance during the compilation process of the kernel, you will not prompt the display mode. This display mode can be set via the LILO or RDEV tool program. 3. The kernel is next to detect other hardware devices, such as hard drives, floppy disks, and NICs, etc., and configure the corresponding device driver. At this time, some hardware information of the kernel run output appears. 4. Next, the kernel is loaded with the root file system. The location of the root file system can be specified when the compile core can also be specified by LILO or RDEV. The type of file system can be automatically detected. If the loading fails due to some reason, the kernel starts failed and eventually terminates the system. 5. Then, init switches to multi-user mode and start a getty process for each virtual console and serial line, and the Getty process manages the login from the virtual console and serial terminal. According to different configurations, INIT can also start other processes.
