directory

Problem description

Troubleshooting Procedure

1. Restart the system to enter single user mode

2. Enter the kernel parameter modification interface, as shown in the following figure

3. Modify kernel parameters

4. Single user mode interface

5. Check the /etc/inittab configuration file

6. Check related services

Solution:

1. Enter the single user mode again and check the startup program

2, delete mysql and mysqld from self-start service

3. Restart the system

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Problem description

Sometimes, we start up our Linux servers, or Linux virtual machines on Vmware

Feel like you didn’t do anything before you turned it off

However, inexplicably, the system is stuck in the startup interface when it starts up, and the login interface for entering user name/password cannot be entered

LIke This left

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Cause analysis,

The system fails to boot for various reasons

System failures, startup level failures, service freezes, and more

Troubleshooting Procedure

Don’t panic if you have a problem. Use single user mode first

1. Restart the system to enter single user mode

On the inner core selection screen, press E (Edit) as shown below

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2. Go to the page for modifying kernel parameters

LIke That left

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3. Modify kernel parameters

Move the cursor to the second line: press E and type quiet 1, or quiet single, to enter single-user mode. Then press B to restart the system and enter single-user mode. Note: e stands for edit and B stands for bootCopy the code

The diagram below:

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4. Single user mode interface

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5. Check the /etc/inittab configuration file

Check to see if there is a problem with the default runtime level of the configuration in /etc/inittab.

If no GRAPHICAL interface is selected during installation

If the inittab level is set to 5, it cannot start normally.

The vast majority of boot failure problems are caused by the boot level.

[root@localhost /]# vim /etc/inittab
Copy the code

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Check result: The startup level is 3, and the command line startup is normal

6. Check related services

Run the command to restart the server

[root@localhost /]# init 3
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It will display the program that was running when the system loaded

If there are any self-booting programs that can’t load, it shows up to help us troubleshoot, okay

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We found that the mysql process has been started……

But he couldn’t get up

The system is stuck on the startup screen and cannot be started

Mysql > select * from mysql

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Solution:

Mysql fails to start automatically, resulting in system startup failure

Disable mysql startup

After successfully entering the system, use lightning 10 whip to clean up mysql

1. Enter the single user mode again and check the startup program

[root@localhost /]# chkconfig | grep mysql
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Sure enough, mysql’s two services are bootstrapped

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2, delete mysql and mysqld from self-start service

[root@localhost /]# chkconfig --del mysql[root@localhost /]# chkconfig --del mysqld
Copy the code

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3. Reboot Restart the system

Reboot After the restart, the login page is displayed

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Always a summary

When the system can not start, do not panic, after eliminating the hardware problem, is certainly the system internal service problem.

Step by step in single-user mode, problems emerge

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