Shulou(Shulou.com)06/01 Report--

Reference: http://www.centoscn.com/mysql/2016/0315/6844.html

Check whether mysql is installed: # rpm-qa | grep-I mysql / / this command will check whether the mysql database has been installed on the operating system-I ignore case and uninstall the original mysql: # rpm-e mysql / / normal delete mode # rpm-e-- nodeps mysql / / strong delete mode, if you delete it using the above command If you are prompted to have other dependent files, you can use this command to delete them and view the mysql version provided by yum: # yum list | grep-I mysql. Then we can install mysql mysql-server mysql-devel by entering the yum install-y mysql-server mysql mysql-devel command (Note: when we install mysql, we do not install the mysql client is equivalent to installing the mysql database. We also need to install the mysql-server server) # yum install-y mysql-server mysql mysql-deve start or stop service # service mysqld stop # service mysqld restart # systemctl enable mysqld # set boot # / usr/bin/mysqladmin-u root password' new-password' / / set the password for the root account # mysql > grant all privileges on *. * to 'root'@' % 'identified by' 123456' with grant option # flush privileges Firewall-cmd (recommended) executes firewall-cmd-- permanent-- zone=public-- add-port=3306/tcp firewall-cmd-- permanent-- zone=public-- add-port=3306/udp so that the corresponding port is opened. Execute firewall-cmd-- reload to make the latest firewall setting rules take effect. Configuration file: # cp / usr/share/mysql/my-default.cnf / etc/my.cnf add [mysqld] character_set_server=utf8 init_connect='SET NAMES utf8' View mysql installed version: mysql-version View enable Port: netstat-ntpl | grep 3306 Note: if it is a rpm download package rpm-ivh example.rpm install example.rpm Package and display the information of the files being installed and the installation progress during the installation process

Pit one: Access denied for user 'root'@'localhost' (using password: NO)

Resolution steps:

1. After stopping the mysql service, service mysql stop, secure startup: mysql_safe-- skip-grant-tables

170310 18:02:36 mysqld_safe Logging to'/ var/lib/mysql/localhost.localdomain.err'.

170310 18:02:36 mysqld_safe Starting mysqld daemon with databases from / var/lib/mysql

2, mysql-u root

Mysql > use mysql

Mysql > update user set password=PASSWORD ("123456") where User='root'

Mysql > grant all privileges on *. * to 'root'@'%' identified by' 123456 'with grant option

Flush privileges

3, service mysql stop; service mysql start

4MySQL-uroot-p; enter the password to log in to ok

5, firewall-cmd-- add-port=3306/tcp-- permanent # Open port 3306

Pit 2: it was found that the CentOS 7 version removed MySQL database software from the default program list and replaced it with mariadb.

There are two solutions:

1. Method 1: install mariadb

MariaDB database management system is a branch of MySQL, which is mainly maintained by the open source community and licensed by GPL. One of the reasons for developing this branch is that after Oracle acquired MySQL, there is a potential risk of shutting down MySQL, so the community uses a branching approach to avoid this risk. The goal of MariaDB is to be fully compatible with MySQL, including API and the command line, making it an easy replacement for MySQL.

Install mariadb, size 59m.

[root@yl-web yl] # yum install mariadb-server mariadb

The relevant commands for the mariadb database are:

Systemctl start mariadb # launch MariaDB

Systemctl stop mariadb # stop MariaDB

Systemctl restart mariadb # restart MariaDB

Systemctl enable mariadb # set boot up

So start the database first.

[root@yl-web yl] # systemctl start mariadb

Then you can use mysql normally.

Method 2: download and install mysql-server on the official website

# wget # rpm-ivh mysql-community-release-el7-5.noarch.rpm# yum install mysql-community-server

Restart the mysql service after successful installation.

# service mysqld restart

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