個人經驗，直奔主題，centos7採用yum安裝mysql-server 避免了各種人爲的處理依賴。
1，下載官方Yum源：http://dev.mysql.com/downloads/repo/
# wget https://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm直接將mysql*.rpm文件下載下來之後執行下列操作
sudo yum localinstall mysql57-community-release-el7-*.noarch.rpm完成上面兩步之後直接進入下一步
sudo yum install mysql-server2，更新/etc/my.cnf或/etc/mysql/my.cnf
因爲更新配置文件可能會依照特定需求修改mysql數據文件及日誌文件等存儲目錄，爲確保mysql用戶對新目錄擁有相應的權限，可在更新配置文件前將原mysql擁有目錄複製至新目錄：
[mysqld]
datadir=/home/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
skip-name-resolve
skip-grant-tables
# Disabling symbolic-links is recommended to prevent assorted security risks
#symbolic-links=0
transaction-isolation=READ-COMMITTED
# Disabling symbolic-links is recommended to prevent assorted security risks;
# to do so, uncomment this line:
# symbolic-links=0
key_buffer = 16M
key_buffer_size = 32M
max_allowed_packet = 16M
thread_stack = 256K
thread_cache_size = 64
query_cache_limit = 8M
query_cache_size = 64M
query_cache_type = 1
# Important: see Configuring the Databases and Setting max_connections
max_connections = 750
# log-bin should be on a disk with enough free space
#log-bin=/x/home/mysql/logs/binary/mysql_binary_log
# For MySQL version 5.1.8 or later. Comment out binlog_format for older versions.
#binlog_format = mixed
read_buffer_size = 2M
read_rnd_buffer_size = 16M
sort_buffer_size = 8M
join_buffer_size = 8M
# InnoDB settings
innodb_file_per_table = 1
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 64M
innodb_buffer_pool_size = 4G
innodb_thread_concurrency = 8
innodb_flush_method = O_DIRECT
innodb_log_file_size = 512M
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
2.3安裝MySQL JDBC Connector
sudo yum install mysql-connector-java
2.4啓動Mysql
sudo service mysqld start
2.5設置Mysql的root密碼，初始密碼爲空（非必須）rootcentos
$ sudo /usr/bin/mysql_secure_installation
[…]
Enter current password for root (enter for none):
OK, successfully used password, moving on…
[…]
Set root password? [Y/n] y
New password:
Re-enter new password:
Remove anonymous users? [Y/n] Y
[…]
Disallow root login remotely? [Y/n] N
[…]
Remove test database and access to it [Y/n] Y
[…]
Reload privilege tables now? [Y/n] Y
All done!
2.6設置Mysql爲開機自動啓動
mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off
2.7爲Cloudera Manager創建MySQL Databases(本人做集羣用)
（1）用root登陸Mysql：$ mysql -u root –p
（2）腳本
create database amon DEFAULT CHARACTER SET utf8;
grant all on amon.* TO ‘amon’@’%’ IDENTIFIED BY ‘amon_password’;
create database smon DEFAULT CHARACTER SET utf8;
grant all on smon.* TO ‘smon’@’%’ IDENTIFIED BY ‘smon_password’;
create database rman DEFAULT CHARACTER SET utf8;
grant all on rman.* TO ‘rman ‘@’%’ IDENTIFIED BY ‘rman_password’;
create database hmon DEFAULT CHARACTER SET utf8;
grant all on hmon.* TO ‘hmon’@’%’ IDENTIFIED BY ‘hmon_password’;
create database hive DEFAULT CHARACTER SET utf8;
grant all on hive.* TO ‘hive’@’%’ IDENTIFIED BY ‘hive_password’;
create database nav DEFAULT CHARACTER SET utf8;
grant all on nav.* TO ‘nav’@’%’ IDENTIFIED BY ‘nav_password’;
（3）執行實例
Create a database for the Activity Monitor. The database name, user name, and password can be anything you want. For example:
mysql> create database amon DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql>grant all on amon.* TO ‘amon’@’%’ IDENTIFIED BY ‘amon_password’;
Query OK, 0 rows affected (0.00 sec)
（3）Create a database for the Service Monitor. The database name, user name, and password can be anything you want. For example:
mysql> create database smon DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql> grant all on smon.* TO ‘smon’@’%’ IDENTIFIED BY ‘smon_password’;
Query OK, 0 rows affected (0.00 sec)
（4）Create a database for the Report Manager. The database name, user name, and password can be anything you want. For example:
mysql> create database rman DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql> grant all on rman.* TO ‘rman ‘@’%’ IDENTIFIED BY ‘rman_password’;
Query OK, 0 rows affected (0.00 sec)
（5）Create a database for the Host Monitor. The database name, user name, and password can be anything you want. For example:
mysql> create database hmon DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql> grant all on hmon.* TO ‘hmon’@’%’ IDENTIFIED BY ‘hmon_password’;
Query OK, 0 rows affected (0.00 sec)
（6）Create a database for the Hive metastore. The database name, user name, and password can be anything you want. For example:
mysql> create database hive DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql> grant all on hive.* TO ‘hive’@’%’ IDENTIFIED BY ‘hive_password’;
Query OK, 0 rows affected (0.00 sec)
（7）Create a database for Cloudera Navigator. The database name, user name, and password can be anything you want. For example:
mysql> create database nav DEFAULT CHARACTER SET utf8;
Query OK, 1 row affected (0.00 sec)
mysql>grant all on nav.* TO ‘nav’@’%’ IDENTIFIED BY ‘nav_password’;
Query OK, 0 rows affected (0.00 sec)
2.8爲Mysql設置備份
使用mysqldump，命令格式如下：
mysqldump-h-u-p>/tmp/.sql
For example, to back up database scm_database on the local host as the root user, with the password mypasswd:
如果你順利的執行到此處，恭喜你，很順利，但是本人在實際中遇到了問題，問題描素就是：
1，Access denied for user ‘root’@’localhost’ (using password: NO)
處理方法：密碼不對
[root ~]# grep 'temporary password' /var/log/mysqld.log
2017-07-05T07:32:13.291107Z 1 [Note] A temporary password is generated for root@localhost: l(0P<cNuwMd1執行之後找到密碼，登錄之後繼續上訴的2.5步驟
2，[ERROR] InnoDB: Unable to lock ./ibdata1 error: 11
[Note] InnoDB: Check that you do not already have another mysqld process using the same InnoDB data
or log files.
處理方法：有進程共用mysqlid
mysqld stop
service mysqld stop
ps -ef|grep mysql*
kill -9 對應的進程id以上基本上可以處理這個問題了之後再重啓mysql （service mysqld start），此時進入上訴2.4步驟
3,service mysql start failed
改問題與上訴2問題類似
# lsof -i:3306查看mysql有沒有進行，之後按照2的處理方式進行處理
4, Failed! Error: Your password does not satisfy the current policy requirements
處理方法： 你的密碼級別很高，重置的密碼級別不高，重設
5,改密碼級別
進入mysql之後
set global validate_password_policy=0;
set global validate_password_length=0;
SET PASSWORD FOR 'root'@'localhost' = PASSWORD('root');