apt-get isntall mysql-client
apt-get libmysqlclient-dev

root@xyz:~# netstat -tap | grep mysql
tcp6    0   0 [::]:mysql       [::]:*         LISTEN   7510/mysqld -->安装成功

vi /etc/mysql/mysql.conf.d/mysqld.cnf 

grant all on *.* to root@'%' identified by 'root' with grant option;
flush privileges;

/etc/init.d/mysql restart

　　mysql -u root
　　mysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpass');

　　mysqladmin -u root password "newpass"

　mysqladmin -u root password oldpass "newpass"

mysql -u root
　　mysql> use mysql;
　　mysql> UPDATE user SET Password = PASSWORD('newpass') WHERE user = 'root';
　　mysql> FLUSH PRIVILEGES;
   在丢失root密码的时候，可以这样
　　 mysqld_safe --skip-grant-tables&
　　 mysql -u root mysql
　　 mysql> UPDATE user SET password=PASSWORD("new password") WHERE user='root';
　　 mysql> FLUSH PRIVILEGES;