This topic describes the problem caused by an error when starting the mysql service. It also expands some other knowledge points. The current version is redhat6 and mysql5.6. Directory overview step error reporting source problem resolution problem analysis system automatic restart service summary step error reporting source Problem Resolution 1. Permission Overview
This article mainly introduces the problem caused by an error when starting the mysql service, along with some other knowledge points. The current version is red hat 6 and mysql 5.6.
Directory
Overview
Procedure
Error source
Problem solving
Problem analysis
The system automatically restarts the service.
Summary
Procedure
Error source
Problem solving
1. permission
The error is reported at the source. Generally, the first problem is the permission problem, that is, the permission of the/var/lib/mysql folder.
You can see that the user and group in the mysql folder are both mysql and mysql has the write permission, so the permission is correct.
2. process
View the/var/lib/mysql Directory. if the mysql. sock file is not found, it indicates that mysql is not started. you can also log on to mysql to test
View process ps-ef | grep mysql
The mysql process is found because it is killed and killed-9 pid
Start the mysql service again. for service mysql start, my current mysql version is 5.6. for service mysql start in mysql 5.7, it is slightly different.
View the mysql directory and find that the mysql. sock file is generated.
Problem analysis
Do you still remember the first error?
The mysql process already exists, but the stop mysql service prompts that the process cannot be found. The main reason is that the mysql process is stored in the process. The solution is to kill these processes according to the preceding command, why does this process occur? Here is my own operation error. mysql was automatically started when the server was started, and then I executed a service mysql start, which caused this problem. this is also the cause of the problem, there are many articles on the Internet to solve this problem, but they have not found out the cause of the problem. There may be other reasons that cause this problem, but here I started the service again, mysql 5.6 does not automatically restart mysql.
The system automatically restarts the service.
Chkconfig command
Run the chkconfig command to query the restart status of the service. run the command chkconfig -- list servername. you can also view all
[0-6] represents the operating mode of the linux system, 0: downtime, 1: Single user mode, 2: non-network users, 3: non-graphic users, 4: not used. 5: In the graphic interface mode x11, you will often see the linux desktop (default level), and 6: restart.
You can use the chkconfig -- level service name on/off method to disable and start the service.
For example, we disable automatic startup of mysql at linux2, 3,4, and 5 running levels,
Chkconfig -- level 2345 mysql off
Here is a good summary of the article on auto start service: overview
This article mainly introduces the problem caused by an error when starting the mysql service, along with some other knowledge points. The current version is red hat 6 and mysql 5.6.
Directory
Overview
Procedure
Error source
Problem solving
Problem analysis
The system automatically restarts the service.
Summary
Procedure
Error source
Problem solving
1. permission
The error is reported at the source. Generally, the first problem is the permission problem, that is, the permission of the/var/lib/mysql folder.
You can see that the user and group in the mysql folder are both mysql and mysql has the write permission, so the permission is correct.
2. process
View the/var/lib/mysql Directory. if the mysql. sock file is not found, it indicates that mysql is not started. you can also log on to mysql to test
View process ps-ef | grep mysql
The mysql process is found because it is killed and killed-9 pid
Start the mysql service again. for service mysql start, my current mysql version is 5.6. for service mysql start in mysql 5.7, it is slightly different.
View the mysql directory and find that the mysql. sock file is generated.
Problem analysis
Do you still remember the first error?
The mysql process already exists, but the stop mysql service prompts that the process cannot be found. The main reason is that the mysql process is stored in the process. The solution is to kill these processes according to the preceding command, why does this process occur? Here is my own operation error. mysql was automatically started when the server was started, and then I executed a service mysql start, which caused this problem. this is also the cause of the problem, there are many articles on the Internet to solve this problem, but they have not found out the cause of the problem. There may be other reasons that cause this problem, but here I started the service again, mysql 5.6 does not automatically restart mysql.
The system automatically restarts the service.
Chkconfig command
Run the chkconfig command to query the restart status of the service. run the command chkconfig -- list servername. you can also view all
[0-6] represents the operating mode of the linux system, 0: downtime, 1: Single user mode, 2: non-network users, 3: non-graphic users, 4: not used. 5: In the graphic interface mode x11, you will often see the linux desktop (default level), and 6: restart.
You can use the chkconfig -- level service name on/off method to disable and start the service.
For example, we disable automatic startup of mysql at linux2, 3,4, and 5 running levels,
Chkconfig -- level 2345 mysql off
There's a good summary of an article about auto start service: http://www.bitsCN.com/ OS /201301/185495.html
View boot. log logs
Command: cat/var/log/boot. log
Boot. log records the log information of the startup item.
Summary
This article mainly describes how to locate the problem when you encounter a problem, and expands some information about automatic startup of the system.
View boot. log logs
Command: cat/var/log/boot. log
Boot. log records the log information of the startup item.
Summary
This article mainly describes how to locate the problem when you encounter a problem, and expands some information about automatic startup of the system.