How to install mysql 5.5 or 5.6 on ubuntu 16.04 xenial_ubuntu16.04支持mysql5.5么-优快云博客

本文链接：https://blog.youkuaiyun.com/hejisan/article/details/81434979

Connect to your server.

Uninstall any existing version of MySQL
```
sudo rm /var/lib/mysql/ -R
```
Delete the MySQL profile
```
sudo rm /etc/mysql/ -R
```

Automatically uninstall mysql

sudo apt-get autoremove mysql* --purge
sudo apt-get remove apparmor

Download version 5.5.51 from MySQL site

wget https://dev.mysql.com/get/Downloads/MySQL-5.5/mysql-5.5.56-linux-glibc2.5-x86_64.tar.gz

Add mysql user group
```
sudo groupadd mysql
```
Add mysql (not the current user) to mysql user group
```
sudo useradd -g mysql mysql
```

Extract to /usr/local

sudo tar -xvf mysql-5.5.56-linux-glibc2.5-x86_64.tar.gz -C /usr/local/

Create mysql folder in /usr/local by moving the untarred folder
```
cd /usr/local
sudo mv mysql-5.5.49-linux2.6-x86_64 mysql
```
Set mysql directory owner and user group
```
cd mysql
sudo chown -R mysql:mysql *
```
Install the required lib package (works with 5.6 as well)
```
sudo apt-get install libaio1
```

Execute mysql installation script

sudo scripts/mysql_install_db --user=mysql

Set mysql directory owner from outside the mysql directory
```
sudo chown -R root .
```
Set data directory owner from inside mysql directory
```
sudo chown -R mysql data
```

Copy the mysql configuration file

sudo cp support-files/my-medium.cnf /etc/my.cnf (mysql 5.5)
sudo cp support-files/my-default.cnf /etc/my.cnf (mysl 5.6)

Start mysql

sudo bin/mysqld_safe --user=mysql &
sudo cp support-files/mysql.server /etc/init.d/mysql.server

Initialize root user password

sudo bin/mysqladmin -u root password '[your new password]'

Add mysql path to the system

sudo ln -s /usr/local/mysql/bin/mysql /usr/local/bin/mysql

Reboot!
Start mysql server
```
sudo /etc/init.d/mysql.server start
```
Stop mysql server
```
sudo /etc/init.d/mysql.server stop
```
Check status of mysql
```
sudo /etc/init.d/mysql.server status
```

Enable myql on startup

sudo update-rc.d -f mysql.server defaults

Disable mysql on startup (Optional)

sudo update-rc.d -f mysql.server remove

REBOOT!
Now directly use the command below to start mysql if it hasn’t
```
sudo service start mysql -u root -p
```
To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

./bin/mysqladmin -u root password 'new-password'
./bin/mysqladmin -u root -h VM-0-14-ubuntu password 'new-password'

Alternatively you can run:
./bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default. This is
strongly recommended for production servers.

See the manual for more instructions.

You can start the MySQL daemon with:
cd . ; ./bin/mysqld_safe &

You can test the MySQL daemon with mysql-test-run.pl
cd ./mysql-test ; perl mysql-test-run.pl

Please report any problems at http://bugs.mysql.com/
Can't connect to local MySQL server through socket '/usr/local/mysql/data/mysql.sock' (111)

启动的原理是，

/home/ubuntu/mysql-5.5.56-linux-glibc2.5-i686/support-files/mysql.server这个文件中定义了my.cnf文件，my.cnf文件中定义了一切

修改my.cnf文件：
在/etc/my.cnf文件中添加如下内容，并重启mysqls服务，即可解决mysql,mysqldump,mysqladmin的“Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock'”问题：

[mysqld]
datadir=/storage/db/mysql
socket=/storage/db/mysql/mysql.sock

[mysql]
socket=/storage/db/mysql/mysql.sock

[client]
socket=/storage/db/mysql/mysql.sock

[mysqldump]
socket=/storage/db/mysql/mysql.sock

[mysqladmin]
socket=/storage/db/mysql/mysql.sock