CentOS7安装MariaDB并配置主从同步
环境声明：
防火墙firewalld及SElinux均为关闭状态
主库节点：192.168.0.63
从库节点：192.168.0.64
配置主库节点：
前提：配置好yum软件安装源
yum install mariadb-server
vim /etc/my.cnf
主库节点mariadb配置文件/etc /my.cnd
[mysqld]
binlog-ignore-db=mysql
binlog-ignore-db=information_schema
log-bin=mysql-bin
server-id=1
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid
#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
配置文件补充说明：
binlog-ignore-db 用来指定忽略同步的数据库，未指定的默认都进行主从复制。
log-bin 指定数据库操作日志，主从复制的过程本质就是从数据库在主数据库读取该日志，并且再执行一次。
server-id 只要满足在数据库集群中不重复即可且必须不能重复
保存退出，重启Mysqld服务，使配置生效。修改到配置文件，最好都重启该配置相关的程序或服务。
systemctl start mariadb
systemctl enable mariadb
mysql_secure_installation
Enter current password for root (enter for none): # 输入数据库超级管理员root的密码(注意不是系统root的密码)，第一次进入还没有设置密码则直接回车
Set root password? [Y/n] # 设置密码，y
New password: # 新密码
Re-enter new password: # 再次输入密码
Remove anonymous users? [Y/n] # 移除匿名用户， y
Disallow root login remotely? [Y/n] # 拒绝root远程登录，n，不管y/n，都会拒绝root远程登录
Remove test database and access to it? [Y/n] # 删除test数据库，y：删除。n：不删除，数据库中会有一个test数据库，一般不需要
Reload privilege tables now? [Y/n] # 重新加载权限表，y。或者重启服务也许
MariaDB [(none)]> show master status\G
*************************** 1. row ***************************
File: mysql-bin.000003 # slave根据此信息进行数据同步
Position: 1208 # slave根据此信息进行数据同步
Binlog_Do_DB:
Binlog_Ignore_DB: mysql,information_schema
1 row in set (0.00 sec)
MariaDB [(none)]>
MariaDB [(none)]> GRANT REPLICATION SLAVE ON . to 'slave'@'192.168.0.64' identified by 'root'
-> ;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> GRANT ALL PRIVILEGES ON . TO 'root'@'192.168.0.63' IDENTIFIED BY 'root' WITH GRANT OPTION;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> GRANT ALL PRIVILEGES ON . TO 'root'@'192.168.0.64' IDENTIFIED BY 'root' WITH GRANT OPTION;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> quit
Bye
[root@cosmo-0-63 yum.repos.d]# systemctl restart mariadb
至此主库配置完毕
配置从库节点：
安装步骤和主库一样
配置文件修改
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
server-id=2 # 添加此行
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd
[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid
#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
然后重启mariadb，进行登陆
执行sql语句：change master to master_host='192.168.0.63',master_user='slave',master_password='root',master_log_file='mysql-bin.000003',master_log_pos=1208;
MariaDB [(none)]> change master to master_host='192.168.0.63',master_user='slave',master_password='root',master_log_file='mysql-bin.000003',master_log_pos=1208;
MariaDB [(none)]> slave start;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Connecting to master
Master_Host: 192.168.0.63
Master_User: slave
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000003
Read_Master_Log_Pos: 1208
Relay_Log_File: mariadb-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: mysql-bin.000003
Slave_IO_Running: Connecting
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 1208
Relay_Log_Space: 245
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 0
1 row in set (0.00 sec)
只有当Slave_IO_Running和Slave_SQL_Running都显示Yes时，才表示主从复制配置成功。否则失败，检查上述配置过程。
主从复制验证：
首先，在主数据建立一个demo数据库，看两个从数据库是否会自动进行复制。
在服务器A登录主数据库，查看现有数据库。
63主库节点：
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
+--------------------+
3 rows in set (0.00 sec)
MariaDB [(none)]> create database demo;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| demo |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)
然后登陆64节点进行查看
能看到在63上创建的demo库则代表配置主从成功
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| demo |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)
THE END