Linux record -4.22 MySQL 5.37 installation (supplementary)

MySQL Official website   https://www.mysql.com/

Community Edition It's free.

Generic General Edition , Normal version

spot Archives Other versions , Enter the optional version number , spot download , Copy download link

install wget Tools

wget download

（ Of course win It's the same when you pass it up and down ）

Delete the system's original mysql（ If any ）.

grep -i  Ignore case .

rpm  -ev  Forcibly delete the packages found

find Check the previous mysql Catalog , And use rm -rf  Delete the folder name

Delete my.cnf , Previously installed configuration files

rm -rf /etc/my.cnf

Unpack the installation

Rename and relocate

Build directory , Data used to place the database .

see mysql Whether users and groups exist , Create if not

/etc/group View groups in

groupadd Create a group

useradd -M -s /sbin/nologin mysql       Create a directory without login , Use the specified after login shell Of MySQL user .

useradd  -g mysql  mysql  Add a new user to a group （ With the -g Then the group name ）.

Appoint shell yes /sbin/nologin Indicates that the user is not logged in , The account is only used for services , For system security .

useradd -M -s /sbin/nologin -g mysql mysql

useradd        Create a user

-M                  Don't automatically create /home/mysql This home directory , This is a User login directory .

                      （ stay /etc/passwd see , Although it will show , But it's red , It's not real , See the picture below ）

-r 　              Set up a system account .

-g    Group name  　 Specify the group to which the user belongs .

-s    Used after login shell name       Specify the... Used by the user after login shell .

                        Set to /sbin/nologin  You cannot log in to the system

                         Set to /bin/bash  You can log in to the system .（ default setting ）

/etc/passwd  View users in

chown Appoint mysql The owner of the data directory . That is, to set the owner , Generic group .

chown -R mysql:mysql  /data/mysql

-R  Express Process all files in the specified directory and its subdirectories

ls -la View hidden files , /data/mysql The primary group of the folder .        . Is this folder            .. Is the upper level folder

Start the display log No settings , Because you don't have write permission .

Another mistake is PID Can't find ,PID It really doesn't exist before it starts .

 

establish mysql.log No more errors will be reported , but PID Because there is no startup, there is still no .

 

 

 

 

Successful startup

At the end of installation A temporary password...... The default... Will be prompted [email protected] User's password .

 [email protected] It means local root user .

At this time, log in directly root The account number reported an error and was not found socket file , although socket The file is already in the defined path /usr/local/mysql/mysql.sock It automatically generates , But I don't know why /tmp/mysql.sock This path looks for .

Now that I know the reason, I will add .

The current processing method is to generate mysql.sock and /tmp/ Make soft connection under .

stay database Under the path /bin start-up mysql , When the password contains ; It's direct   -p+ Passwords plaintext   The way of writing will be wrong , The system will assume that the command has ended by the semicolon .

Therefore, the password can only be entered through ciphertext . Landing successful .

When you log in, you will be prompted to use alter user To change the password to execute other commands .

The database also prompts like this .

direct alter user root Will fail , This is for Other than the current user User settings .

alter user user() To change The current user Password .

Modify the format of account and password （mysql5.7 Above version ）

alter user user name identified by ' New password ';