RedHat 6 Installing MySQL 5.5 process records and related problem solutions

[TOC]

1. Install MySQL1.1 in RedHat using Yum mode to remove the system's own MySQL 5.1

rpm|grep mysql   #查看已经安装的mysqlrpm -e mysql　　          #普通删除模式rpm -e --nodeps mysql  #强力删除模式

1.2 Uninstall RPM package with Yum to prevent MySQL installation conflicts

yum -y remove mysql-libs-5.1.66*

1.3 Creating a local Yum repository configuration

vi /etc/yum.repos.d/local.repo

Add the following section:

[localrepo]name = myLocalYumRepobaseurl = /home/rhel/Downloads/MySQL-5.5.58-l.el6-rpmgpgcheck = 0enable = 1

baseurlit points to the path where my MySQL RPM package is located.

1.4 Yum Install MySQL

Once configured local_yum_repo , cd enter baseurl the directory where you can install the following three:

yum install MySQL-server-5.5.58-1.el6.x86_64.rpmyum install MySQL-client-5.5.58-1.el6.x86_64.rpmyum install MySQL-devel-5.5.58-1.el6.x86_64.rpm

1.4.1 Uninstalling MySQL

Use the command to see what MySQL programs have been installed:

rpm -qa|grep -i mysql

Use the RPM installation to uninstall using the following command:

rpm -ev MySQL-client-5.5.58-1.el6.x86_64 --nodepsrpm -ev MySQL-devel-5.5.58-1.el6.x86_64 --nodepsrpm -ev MySQL-server-5.5.58-1.el6.x86_64 --nodeps

To find the original MySQL directory:

find / -name mysql

Find the following to delete:

rm -rf /usr/lib64/mysqlrm -rf /var/lib/mysqlrm -rf /var/lib/mysql/data/mysqlrm -rf /var/lib/mysql/mysql

Manually delete/etc/my.cnf

Finally, check it out again. MySQL installed:

rpm -qa|grep -i mysql

If it is not displayed, it is already uninstalled.

1.5 Description of the directory after installation

After installation MySQL main default storage file directory:

/usr/bin                 #这里存放脚本和客户端程序/var/lib/mysql        #mysql的数据存储目录/usr/share/mysql  #mysql存放的初始化相关脚本

1.6 MySQL configuration file

Edit:vi /etc/my.cnf

# The MySQL Client[client]#客户端默认连接字集集,若编译安装时已指定则不用填写#character-set-server = utf8#客户端连接通信端口port = 3306#客户端通信的用户密码端口等信息保存文件socket = /var/lib/mysql/mysql.sockdefault-character-set=utf8# The MySQL server[mysqld]#mysql服务端监听端口port  = 3306     #mysql数据库存放目录datadir = /var/lib/mysql/datasocket = /var/lib/mysql/mysql.sock#服务端pid进程文件,若丢失则重启Mysql重新生成,若重启失败,#则可能由于mysqld进程未杀死,用pkill mysql后则能重启成功Mysql#pid-file =/opt/mysql/data/myDBserver.pidbind-address = 0.0.0.0[mysql]socket = /var/lib/mysql/mysql.sock

1.7 Initializing MySQL

Use the default path:

/usr/bin/mysql_install_db --user=mysql

1.8 Modify MySQL directory owner and user group to "MySQL"

chown -R mysql /var/lib/mysql/chgrp -R mysql /var/lib/mysql/

1.9 Starting and stopping MySQL

To start the MySQL service:

#/etc/init.d/mysqld start  # rhel 没有这个命令/etc/init.d/mysql start

To stop the MySQL service:

/etc/init.d/mysql stop

1.10 Modify the default password for the MySQL root user

(1) Mode 1:

1. Use the command first: mysql go to MySQL

2. Execute SQL statement to update root password

sql update mysql.user set password=PASSWORD(‘Cs123456‘) where user=‘root‘;

1. Refresh the permissions, then you can.

sql flush privileges;

(2) Mode 2:

Another way to modify the root user password is to execute the shell command:

mysqladmin -u root password Cs123456

1.11 Log in to MySQL command format

mysql [-u username] [-h host] [-p[password]] [dbname]

For example:

mysql -u root -pCs123456 -h localhost

1.12 Remote connection Authorization for root

mysql -uroot -p'Cs123456'GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;FLUSH PRIVILEGES;

If you do not want to authorize a remote connection to root, we can create a new user specifically for use as a remote connection, such as "test":

createuseridentifiedby'Cs123456';grantallprivilegesonto'test'@'%'by'Cs123456'withgrantoption;flushprivileges;

@‘%‘It means to open all IP addresses.

To modify a user's password, use the following statement:

updateset password=password('新密码'where User="test"and Host="localhost";flushprivileges;

To delete a user:

deletefromuserwhere User='test'and Host='localhost';flushprivileges;

1.13 Troubleshooting MySQL's inability to connect remotely

vi /etc/my.cnf

Will bind-address = 127.0.0.1 , set tobind-address = 0.0.0.0

2. Problems encountered during installation ★error! MySQL server PID file could not being found!

Cause: The MySQL process is stuck dead.
Workaround:

1.杀死mysql进程：killall mysqld2.重启mysql：service mysql start

★error 2002 (HY000): Can ' t connect to local MySQL server through socket '/var/lib/mysql/tmp/mysql.sock '

Cause: mysql.sock The file may not be in the correct location

Workaround:

1, first find mysql.sock the location:

lsof -c mysqld|grep sock$

This path was found:/var/lib/mysql/mysql.sock

2 vi /etc/my.cnf . Configure and change the path of the socket to the [mysqld] [mysql] [client] path found above.

★starting MySQL. error! The server quit without updating PID file (/var/lib/mysql/data/mydbserver.pid

Possible causes: last MySQL abnormal shutdown

Workaround: Create a mydbserver.pid empty file and arbitrarily set a PID that is not in the process

vi /var/lib/mysql/data/myDBserver.pid23432

Then restart the MySQL service, if there is no other reason, it can start normally.

★ About remote access MySQL appears access denied for user ' root ' @ '

Two situations can cause this problem:

(1) root password input error

(2) There is no authorization to open the root external remote connection on the MySQL server. The solution can be consulted (1.)

★ Configure firewall, turn on port 3306

First look at the firewall open ports:

iptables -nL --line-number

Show drop on behalf of firewall blocked Port 3306.

Change the firewall and release port 3306:

vim /etc/sysconfig/iptables

On the COMMIT line, add the following:

-A INPUT -p tcp -m tcp --dport 3306 -j ACCEPT

To restart the firewall:

service iptables restart

See if 3306 becomes ACCEPT , and if so, the port is already open.

RedHat 6 Installing MySQL 5.5 process records and related problem solutions