为了实现mariadb的高可用，常用的有主从复制，和双主复制，双主复制的好处是可以充分利用硬件资源。
约定：
node1IP：192.168.1.100 MariaDB：10.3.15
node2IP：192.168.1.101 MariaDB：10.3.15

基于SSL实现Mysql加密的主从复制配置
Mariadb二进制安装和配置说明
CentOS 7安装 LNMP（Linux+Nginx+MariaDB+PHP）

一、放行Mariadb3306端口，修改Mariadb配置文件，注意是在server.cnf的【server】，MySQL和MariaDB配置文件略有不同

###放行Mariadb3306端口
[root@localhost ~]# firewall-cmd --zone=public --add-port=3306/tcp --permanent
[root@localhost ~]# firewall-cmd --reload


###node1
[root@localhost ~]# vi /etc/my.cnf.d/server.cnf 
[server]
server-id = 1
log-bin = mysql-bin
relay-log = relay-bin


###node2
[root@localhost ~]# vi /etc/my.cnf.d/server.cnf 
[server]
server-id = 2
log-bin = mysql-bin
relay-log = relay-bin

二、在node1和node2上，分别执行以下命令，创建主从复制用户slaveuser并设定密码，如果只需要主从复制不需要双主复制，只需要在Mariadb 主节点 执行即可。

MariaDB [mysql]>grant replication slave,replication client on *.* to 'slaveuser'@'%' identified by '123456';

三、查看mariadb数据库的master状态信息

###node1 需要的两个东西File：mysql-bin.000004 和Position：245807，在创建同步并开启同步会用到。

MariaDB [mysql]> show master status;
+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000004 |   245807 |              |                  |
+------------------+----------+--------------+------------------+

###node2

MariaDB [mysql]> show master status;
+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000004 |     1421 |              |                  |
+------------------+----------+--------------+------------------+

四、创建同步并开启同步，如果只需要主从复制不需要双主复制，只需要在Mariadb 从节点 执行即可。

###node1节点

MariaDB [mysql]>change master to master_host='192.168.1.101',master_user='slaveuser',master_password='123456',master_log_file='mysql-bin.000004',master_log_pos=1421;

MariaDB [mysql]>start slave;

###node2节点
MariaDB [mysql]>change master to master_host='192.168.1.100',master_user='slaveuser',master_password='123456',master_log_file='mysql-bin.000004',master_log_pos=245807;

MariaDB [mysql]>start slave;

五、验证同步信息： Slave_IO_Running: Yes/ Slave_SQL_Running: Yes，必须均为Yes状态才行。

验证一：

###node1

MariaDB [mysql]> show slave status\G;
*************************** 1. row ***************************
                Slave_IO_State: Waiting for master to send event
                   Master_Host: 192.168.1.101
                   Master_User: slaveuser
                   Master_Port: 3306
                 Connect_Retry: 60
               Master_Log_File: mysql-bin.000004
           Read_Master_Log_Pos: 266651
                Relay_Log_File: relay-bin.000002
                 Relay_Log_Pos: 21399
         Relay_Master_Log_File: mysql-bin.000004
              Slave_IO_Running: Yes   此项为yes  
             Slave_SQL_Running: Yes   此项为yes

###node2

MariaDB [mysql]> start slave;
Query OK, 0 rows affected (0.001 sec)

MariaDB [mysql]> show slave status\G;
*************************** 1. row ***************************
                Slave_IO_State: Waiting for master to send event
                   Master_Host: 192.168.1.100
                   Master_User: slaveuser
                   Master_Port: 3306
                 Connect_Retry: 60
               Master_Log_File: mysql-bin.000004
           Read_Master_Log_Pos: 1421
                Relay_Log_File: relay-bin.000002
                 Relay_Log_Pos: 555
         Relay_Master_Log_File: mysql-bin.000004
              Slave_IO_Running: Yes
             Slave_SQL_Running: Yes

验证二、在node1创建测试数据库abc，并在node2节点查看

###node1节点：

MariaDB [mysql]> create database abc;
Query OK, 1 row affected (0.000 sec)

MariaDB [mysql]> show databases;
+--------------------+
| Database           |
+--------------------+
| abc                |
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
6 rows in set (0.000 sec)

###在node2节点查看

MariaDB [mysql]> show databases;
+--------------------+
| Database           |
+--------------------+
| abc                |
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
6 rows in set (0.001 sec)

###在node2节点创建测试数据库，并在node1节点查看，省略。


###测试通过说明MariaDB双主成功

报错处理，如果同步不成功，尝试以下操作，先停止同步，然后重置同步，并重复步骤 一至五 双主复制的操作。

MariaDB [mysql]> stop slave;
MariaDB [mysql]> reset slave;

至此，Mariadb双主同步复制配置完毕。