安装centos时选择安装Mysql 服务器
mysql的默认登录密码为空，但是直接登录的时候有报错：
[root@localhost bin]# mysql -u root -p
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
应该是没有起mysql服务。
先查看mysql服务的状态：
[root@localhost bin]# /etc/rc.d/init.d/mysqld status
mysqld 已停
启动mysql服务：
[root@localhost bin]# /etc/rc.d/init.d/mysqld start
初始化 MySQL 数据库： WARNING: The host 'xxaq' could not be looked up with resolveip.
This probably means that your libc libraries are not 100 % compatible
with this binary MySQL version. The MySQL daemon, mysqld, should work
normally with the exception that host name resolving will not work.
This means that you should use IP addresses instead of hostnames
when specifying MySQL privileges !
Installing MySQL system tables...
OK
Filling help tables...
OK
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:
/usr/bin/mysqladmin -u root password 'new-password'
/usr/bin/mysqladmin -u root -h xxaq password 'new-password'
Alternatively you can run:
/usr/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 /usr ; /usr/bin/mysqld_safe &
You can test the MySQL daemon with mysql-test-run.pl
cd /usr/mysql-test ; perl mysql-test-run.pl
Please report any problems with the /usr/bin/mysqlbug script!
[确定]
正在启动 mysqld： [确定]
查看mysql状态
[root@localhost bin]# ps -aef|grep mysql
root 17468 1 0 08:57 pts/1 00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock --pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr --user=mysql
mysql 17573 17468 0 08:57 pts/1 00:00:00 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --log-error=/var/log/mysqld.log --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/lib/mysql/mysql.sock
root 17600 17169 0 08:57 pts/1 00:00:00 grep mysql
此时再登录，没有报错：
[root@localhost bin]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 2
Server version: 5.1.73 Source distribution
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owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
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