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This article will explain in detail the example analysis of managing linux boot service. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

Self-starting services are very important, such as

(1) you need to manually add the service you want to start automatically. If you do not add it automatically after installing svn, you need to add it manually.

(2) after installing some programs, it is automatically added to self-startup, but we do not need to remove it manually.

(3) many malicious programs will add themselves to self-startup, which need to be checked and deleted.

The principle of running level

When it comes to self-starting operations, you will be exposed to the seven directories of / etc/rc.d/rc [0-6] .d

These directories represent the seven runtime levels of linux

The / etc/inittab file specifies which level to enter by default when the system starts

After Linux enters the run level, it will enter the corresponding rcN.d directory and retrieve the files in the directory according to the order of file names.

The rcN.d directory is full of linked files that point to service script files in the / etc/init.d directory, such as

The naming rules are:

Kroomnn+ service name, or Signornn+ service name

The K-system will terminate the corresponding service.

S-the system will start the corresponding service

Nn-two digits, execution order

What are the 7 runlevels?

0. Stop

1. Single-user mode, root permission, for system maintenance, no remote login

2. Multi-user status, no NFS

3. Standard multi-user mode, enter command line mode after login

4. The system is not in use and is retained.

5. Multi-user graphics mode, enter graphics GUI mode after login

6. Restart

Servers are generally in command line mode, so the default run level is 3

How do I add a self-booting program?

(1) add to / etc/init.d directory

Take starting SVN as an example

1) create a script to start the service under the / etc/init.d directory

Vim / etc/init.d/svn

Content

#! / bin/bash

Svnserve-d-r / svn warehouse path

Set execution permissions

Chmod 755 / etc/init.d/svn

2) soft link this script to / etc/rc.d/rc3.d

Ln-s / etc/init.d/svn / etc/rc.d/rc3.d/S101svn

S stands for the script to be executed. 101 is the execution order, usually greater than 60, which ensures that the basic services have been started.

Restart the linux test

(2) add to / etc/rc.local file

Modify / etc/rc.local directly

The script is executed after the system initialization level script runs, so you can add scripts that you want to execute after the system starts

(3) add chkconfig command

How to disable self-starting programs?

(1) directly delete the target link file in the / etc/rc.d/rcN.d directory

(2) delete the startup script defined in / etc/rc.local file

(3) View the list of self-starting services and select the target service to perform the forbidden operation.

Chkconfig-list

Chkconfig-del service name

This is the end of the article on "sample Analysis of Managing linux Boot Service". I hope the above content can be helpful to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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