Note: This article mainly describes how to install mysql5.7.2 on CentOS 7. It is best to set SELINUX=disabled in the system / etc/selinux/config file before installation
Compressed version installation
1 view operating system version
cat /etc/redhat-release
2 environmental preparation before installation
Check whether mysql has been installed
First, check whether MySQL is installed in the Linux operating system:
rpm -qa | grep -i mysql
Uninstall installation package
If any information appears, delete it. The command is as follows:
rpm -e --nodeps Package name
Delete the development header files and libraries of the old version of mysql
rpm -e --nodeps Package name
Note: after uninstallation, the data in / var/lib/mysql and / etc/my.cnf will not be deleted. If it is determined to be useless, delete it manually:
rm -f /etc/my.cnf rm -fr /var/lib/mysql
After the deletion is completed, the installation can be carried out, otherwise the installation will make an error.
Also check the old mysql installation directory
whereis mysql
Delete old installation directory
rm -rf catalogue
3. Create a new soft directory (soft is a directory specially created by myself for storing uploaded tar compressed packages)
cd ~ mkdir soft cd soft/
4 installation process
4.1 installation package preparation
Before installation, prepare the compressed installation package or download it from the mysq official website, and upload the installation package to the root/soft / directory
Provide mysql installation package network disk resources
Link: https://pan.baidu.com/s/1riVvgzoGe9RXI2Qea4Y4eQ
Extraction code: yyds
4.2 unzip to the specified directory
tar -zxvf installation package - C /usr/local
tar -zxvf mysql-5.7.20-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
The directory name is too long. Rename it to mysql
mv mysql-5.7.20-linux-glibc2.12-x86_64 mysql
Create a new directory data under the mysql directory
4.3 view mysql users and groups. If they exist, they need to be deleted
Check whether the mysql user or group exists
id mysql
To delete users and groups:
groupdel mysql userdel -f mysql
If not, go to vi /etc/grpup to find mysql and add#
As follows, there are no users
4.4 add mysql user groups and users, and associate mysql users with mysql groups
Create mysql group
groupadd mysql
Check whether the creation is successful
cat /etc/group | grep mysql
Create mysql user
useradd -r -g mysql mysql
Check whether the creation is successful
cat /etc/passwd | grep mysql
Set password for mysql user: mengxuegu1234
passwd mysql
4.5 authorize mysql to read, write and execute necessary files
chown -R mysql:mysql /usr/local/mysql chmod -R 775 /usr/local/mysql
4.6 enter the contents of MySQL / support files folder
Check whether there is a my-default.cnf configuration file. If there is no default configuration file, you need to manually create a my-default.cnf configuration file
4.7 the content of my-default.cnf configuration file can be directly copied as follows
vi my-default.cnf
[client] port = 3306 socket = /tmp/mysql.sock [mysqld] #mysql installation directory basedir = /usr/local/mysql #data in mysql installation directory datadir = /usr/local/mysql/data bind-address = 0.0.0.0 port = 3306 socket = /tmp/mysql.sock skip-external-locking key_buffer_size = 128M max_allowed_packet = 1M table_open_cache = 256 sort_buffer_size = 1M read_buffer_size = 1M read_rnd_buffer_size = 2M myisam_sort_buffer_size = 8M thread_cache_size = 8 query_cache_size= 16M max_connections = 213 wait_timeout = 31536000 interactive_timeout = 30 max_connect_errors = 9 long_query_time = 1 tmp_table_size = 16M #log-bin=mysql-bin #binlog_format=mixed #server-id = 1 lower_case_table_names = 1 [mysqldump] quick max_allowed_packet = 8M [mysql] no-auto-rehash [myisamchk] key_buffer_size = 12M sort_buffer_size = 1M read_buffer = 1M write_buffer = 1M [mysqlhotcopy] interactive-timeout
4.8 reauthorization
chown -R mysql:mysql /usr/local/mysql chmod -R 775 /usr/local/mysql
4.9 copy my-default.cnf and mysql.server under the support files file as follows
cp my-default.cnf /etc/my.cnf cp mysql.server /etc/init.d/mysqld
4.10 edit mysqld and modify it to the specified path of mysql
vi /etc/init.d/mysqld
Enter the editing page, press i to edit and modify, press ctrl+c to stop the modification, and then: wq save the modification
4.11 add the mysql path to the environment variable to facilitate the operation of commands
vi /etc/profile
Add at the end of file
export MYSQL=/usr/local/mysql export PATH=$PATH:$MYSQL/bin:
4.12 make the modified profile file effective
source /etc/profile
4.13 perform database initialization
The execution file is MySQL in the bin folder under mysql_install_db
basedir is the installation directory and datadir is the data file directory.
Note: mysql_install_db is located in the scripts folder in version 5.6, which has been cancelled in 5.7 and merged into bin:
cd /usr/local/mysql/bin
./mysqld --basedir=/usr/local/mysql --user=mysql --datadir=/usr/local/mysql/data --initialize
The above installation is successful
If error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory is reported, libaio needs to be installed
yum install libaio
If [error] - initialize specified but the data directory has files in it. Aborting
Note: it has been executed once. The '/ usr/local/mysql/data directory needs to be deleted, re created and re authorized
[root@centOS mysql]# cd /usr/local/mysql [root@centOS mysql]# rm -rf data [root@centOS mysql]# mkdir data [root@centOS mysql]# chown -R mysql:mysql /usr/local/mysql [root@centOS mysql]# chmod -R 775 /usr/local/mysql [root@centOS mysql]#
Then execute:
cd /usr/local/mysql/bin
./mysqld --basedir=/usr/local/mysql --user=mysql --datadir=/usr/local/mysql/data --initialize
4.14 after completion, start the mysql service
service mysqld start
At this time, the service can be started, but the whole project is only half completed.
Note: the new version may report an error because mysqld_ Because of safe, there is no error when installing the old version. You just need to put mysqld_ Modify the default path in safe to your own target path, and then execute it.
5. Change password
5.1 shut down the service first
service mysqld stop
5.2 MySQL / bin / mysqld_ Replace usr/local/mysql in safe with the specified installation path name, and then execute the following code.
mysqld_safe --user=mysql --skip-grant-tables --skip-networking &
At this time, it has entered the filter free state and started to modify the root password. Note: the password field in the user table of version 5.6 is password, which is changed to authentication after 5.7_ String, no more password.
The password set above is the root password for us to log in to mysql
[root@localhost bin]# mysql
mysql> use mysql;
mysql> update user set authentication_string=PASSWORD('root') where user='root';
mysql> flush privileges;
mysql> exit;
At this point, the password has been modified. Log out and log in again. I thought it was done, but an error was reported when creating the database. The error is: ERROR 1820 (HY000): You must reset your password using ALTER USER statement. The original first login, but also to set the password again, after modification, the creation is successful.
mysql -u root -p mysql> alter user 'root'@'localhost' identified by 'root'; mysql> flush privileges; mysql> exit;
Set remote login permissions
If you log in through a remote connection, an error will be reported
As follows:
1. Determine the mysql port number,
mysql> show global variables like 'port';
0 is 3306 by default
If it is not 3306, you can modify the mysql port number
1.# vi /etc/my.cnf 2.modify port=3306 3.restart # service mysqld restart
2. Modify the remote connection permission,
Very simple, you only need to modify the host of the root user in the user table. After the change, remember to restart the service and connect remotely again
# mysql -uroot -p mysql> use mysql; mysql> update user set host='%' where user='root'; mysql> exit; # service mysqld restart
3 turn off the firewall,
If 10060 unknown error is not reported, close it
The default firewall of CentOS 7. X is firewall instead of iptables
Check the firewall status (not running is displayed when it is turned off and running is displayed when it is turned on)
firewall-cmd --state
Stop firewall
systemctl stop firewalld.service
Disable firewall startup
systemctl disable firewalld.service
The default firewall of CentOS6 is iptables
1. The firewall takes effect immediately and recovers after restart:
close
service iptables stop
open
service iptables start
2. The firewall takes effect permanently and will not be restored after restart
close:
chkconfig iptables off
On:
chkconfig iptables on