Ubuntu Linux Service Management program: sysv-rc-conf Introduction

Introduction of Sysv-rc-conf

Sysv-rc-conf is a powerful service management program.

Second, background knowledge

Ubuntu Run level

The Linux system runs at a specified run level at all times, and different running levels of programs and services are different, the work to be done and the purpose to be achieved are different, and the system can switch between these run levels to accomplish different tasks.

Ubuntu's system Run level:

0 System shutdown Status

1 single user or system maintenance status

2~5 Multi-user status

6 reboot

View current run level, execute command: runlevel

(RunLevel displays the last run level and the current run level, and "N" indicates that there is no last run level.) )

Switch run level, execute command: int [0123456Ss]

(That is, after the init command followed by a parameter, which is the run-level code to switch to, such as: Shutdown with init 0 command; Restart with the Init 6 command.) )

Linux System main Boot steps:

1. Read the MBR information and start boot Manager

Windows uses NTLDR as the Boot Manager if you have more than one installation on your system

Version of Windows, you will need to select the system you want to enter in the NTLDR.

Linux typically uses a powerful, flexible configuration of GRUB as the Boot Manager.

2. Load system kernel, start init process

The init process is the root process of Linux, and all system processes are its child processes.

3. The init process reads the information in the/etc/inittab file and goes to the preset run level.

Run the script under the corresponding folder in the run level in order. Scripts are usually set with the start argument

Move and point to a program in a system.

Typically, a startup script under the/etc/rcs.d/directory is executed first, followed by

/etc/rcn.d/directory. For example, if you set a run level of 3, it corresponds to the startup

The directory is/etc/rc3.d/.