CentOS 利用Yum安装mysql后无法启动(MySQL Daemon failed to start.)

[root@iZwz9cl4i8oy1reej7o8pmZ ~]# yum install -y mysql-server

[root@iZwz9cl4i8oy1reej7o8pmZ ~]# /etc/init.d/mysqld start
MySQL Daemon failed to start.
Starting mysqld:                                           [FAILED]
[root@iZwz9cl4i8oy1reej7o8pmZ ~]# 

[root@iZwz9cl4i8oy1reej7o8pmZ ~]# cd /etc/
[root@iZwz9cl4i8oy1reej7o8pmZ etc]# mysql_install_db 
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 iZwz9cl4i8oy1reej7o8pmZ 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!
[root@iZwz9cl4i8oy1reej7o8pmZ etc]# 

[root@iZwz9cl4i8oy1reej7o8pmZ ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 
Server version: 5.1. Source distribution
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Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
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