docker搭建mariadb主从

第一步，启动mariadb镜像为主节点，名称为mydb1，并且映射mariadb配置文件目录

[root@bogon conf]# docker run --name mydb1 -itd -e MYSQL_ROOT_PASSWORD=root -v /mydb1/conf/:/etc/mysql/conf.d/ mariadb      
12d8b3c6053a623becd09510d536159c2840c82b0266f474517c3604a1635b03

第二步，启动mariadb镜像为从节点，名称为mydb2，并且映射mariadb配置文件目录

[root@bogon conf]# docker run --name mydb2 -itd -e MYSQL_ROOT_PASSWORD=root -v /mydb2/conf/:/etc/mysql/conf.d/ mariadb   
4e0bfee1a120702c47062ffd7b0ef7272e3ba2a8e0d397f9a2d855b41f33d548

第三步，编辑宿主机master和slave数据库的配置文件

[root@bogon ~]# vim /mydb1/conf/my.cnf
    [mysqld]
    server_id=1
    log_bin=mysql-bin
[root@bogon ~]# vim /mydb2/conf/my.cnf
    [mysqld]
    server_id=2

第四步，重启mydb1和mydb2容器

[root@bogon ~]# docker ps 
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
4e0bfee1a120        mariadb             "docker-entrypoint.s…"   3 minutes ago       Up 3 minutes        3306/tcp            mydb2
12d8b3c6053a        mariadb             "docker-entrypoint.s…"   5 minutes ago       Up 5 minutes        3306/tcp            mydb1
[root@bogon ~]# docker restart mydb1 
mydb1
[root@bogon ~]# docker restart mydb2
mydb2

第五步，mydb1验证

[root@bogon ~]# docker exec -it mydb1 /bin/bash

root@12d8b3c6053a:/# mysql -uroot -proot
Welcome to the MariaDB monitor.  Commands end with ; or g.
Your MariaDB connection id is 9
Server version: 10.4.12-MariaDB-1:10.4.12+maria~bionic-log mariadb.org binary distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

MariaDB [(none)]> show master status;
+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000001 |      328 |              |                  |
+------------------+----------+--------------+------------------+
1 row in set (0.000 sec)

MariaDB [(none)]> show variables like '%%log_bin%';
+---------------------------------+--------------------------------+
| Variable_name                   | Value                          |
+---------------------------------+--------------------------------+
| log_bin                         | ON                             |
| log_bin_basename                | /var/lib/mysql/mysql-bin       |
| log_bin_compress                | OFF                            |
| log_bin_compress_min_len        | 256                            |
| log_bin_index                   | /var/lib/mysql/mysql-bin.index |
| log_bin_trust_function_creators | OFF                            |
| sql_log_bin                     | ON                             |
+---------------------------------+--------------------------------+
7 rows in set (0.002 sec)

mydb2验证

[root@bogon ~]# docker exec -it mydb2 /bin/bash

root@4e0bfee1a120:/# mysql -uroot -proot 
Welcome to the MariaDB monitor.  Commands end with ; or g.
Your MariaDB connection id is 8
Server version: 10.4.12-MariaDB-1:10.4.12+maria~bionic mariadb.org binary distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

MariaDB [(none)]> 
MariaDB [(none)]> show variables like '%server_id%';      
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 2     |
+---------------+-------+
1 row in set (0.002 sec)

第六步，master中创建同步账号，用户名为slave，密码为slave

MariaDB [(none)]> grant all privileges on *.* to slave@'%' identified by 'slave';
Query OK, 0 rows affected (0.003 sec)

第七步，确认mydb1和mydb2数据库的ip地址

[root@bogon ~]# docker inspect -f {{.NetworkSettings.IPAddress}} mydb1
172.17.0.2
[root@bogon ~]# docker inspect -f {{.NetworkSettings.IPAddress}} mydb2
172.17.0.3

第八步，在slave数据库中登录数据同步账号

MariaDB [(none)]> CHANGE MASTER TO MASTER_HOST='172.17.0.2', MASTER_USER='slave', MASTER_PASSWORD='slave', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=511;     
Query OK, 0 rows affected (0.015 sec)

MariaDB [(none)]> start slave;
Query OK, 0 rows affected (0.005 sec)

MariaDB [(none)]> show slave statusG
*************************** 1. row ***************************
                Slave_IO_State: Waiting for master to send event
                   Master_Host: 172.17.0.2
                   Master_User: slave
                   Master_Port: 3306
                 Connect_Retry: 60
               Master_Log_File: mysql-bin.000001
           Read_Master_Log_Pos: 511
                Relay_Log_File: mysqld-relay-bin.000002
                 Relay_Log_Pos: 555
         Relay_Master_Log_File: mysql-bin.000001
              Slave_IO_Running: Yes
             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: 511
               Relay_Log_Space: 865
               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: 0
 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: 1
                Master_SSL_Crl: 
            Master_SSL_Crlpath: 
                    Using_Gtid: No
                   Gtid_IO_Pos: 
       Replicate_Do_Domain_Ids: 
   Replicate_Ignore_Domain_Ids: 
                 Parallel_Mode: conservative
                     SQL_Delay: 0
           SQL_Remaining_Delay: NULL
       Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
              Slave_DDL_Groups: 0
Slave_Non_Transactional_Groups: 0
    Slave_Transactional_Groups: 0
1 row in set (0.000 sec)

第九步，验证两个数据库是否同步，我们在mydb1中创建一个testdb1数据库，看mydb2有没有相同数据库

mydb1操作如下：

MariaDB [(none)]> create database testdb1 character set utf8;
Query OK, 1 row affected (0.001 sec)

mydb2操作如下：

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| testdb1            |
+--------------------+

ok，没有问题！！！