這篇文章介紹一下使用容器化方式構成一主兩從的MySQL數據庫。
docker-compose.yml
liumiaocn:mysql liumiao$ cat docker-compose.yml
version: '2'
services:
master:
image: liumiaocn/mysql:5.7.16
environment:
- MYSQL_ROOT_PASSWORD=liumiaocn
restart: always
ports:
- "3306:3306"
slave1:
image: liumiaocn/mysql:5.7.16
environment:
- MYSQL_ROOT_PASSWORD=liumiaocn
restart: always
ports:
- "3307:3306"
slave2:
image: liumiaocn/mysql:5.7.16
environment:
- MYSQL_ROOT_PASSWORD=liumiaocn
restart: always
ports:
- "3308:3306"
liumiaocn:mysql liumiao$
步驟1: 啓動服務
liumiaocn:mysql liumiao$ docker-compose up -d
Creating network "mysql_default" with the default driver
Creating mysql_slave2_1 ... done
Creating mysql_master_1 ... done
Creating mysql_slave1_1 ... done
liumiaocn:mysql liumiao$ docker-compose ps
Name Command State Ports
-----------------------------------------------------------------------------
mysql_master_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3306->3306/tcp
mysql_slave1_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3307->3306/tcp
mysql_slave2_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3308->3306/tcp
liumiaocn:mysql liumiao$
步驟2: 設定Master節點
設定serverid和log-bin
- 修改對象文件：/etc/mysql/my.cnf
- 添加如下內容：
[mysqld]
log-bin=mysql-bin
server-id=1
執行日誌如下：
liumiaocn:mysql liumiao$ docker exec -it mysql_master_1 sh
# cd /etc/mysql
# ls
conf.d my.cnf my.cnf.fallback mysql.cnf mysql.conf.d
# cp -p my.cnf my.cnf.org
# cat <<EOF >>my.cnf
> [mysqld]
log-bin=mysql-bin
server-id=1> >
> EOF
# diff my.cnf my.cnf.org
18,20d17
< [mysqld]
< log-bin=mysql-bin
< server-id=1
#
設定複製用戶和權限
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.16 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> create user 'replicationuser'@'%' identified by 'replicationuser';
Query OK, 0 rows affected (0.01 sec)
mysql> grant replication slave on *.* to 'replicationuser'@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> show master status;
Empty set (0.01 sec)
mysql>
步驟3: 設定Slave節點
設定Slave1的serverid
liumiaocn:mysql liumiao$ docker exec -it mysql_slave1_1 sh
# cd /etc/mysql
# ls
conf.d my.cnf my.cnf.fallback mysql.cnf mysql.conf.d
# cp my.cnf my.cnf.org
# cat <<EOF >>my.cnf
> [mysqld]
server-id=2>
> EOF
# diff my.cnf my.cnf.org
18,19d17
< [mysqld]
< server-id=2
#
設定Slave2的serverid
liumiaocn:mysql liumiao$ docker exec -it mysql_slave2_1 sh
# cd /etc/mysql
# ls
conf.d my.cnf my.cnf.fallback mysql.cnf mysql.conf.d
# cp my.cnf my.cnf.org
# cat <<EOF >>my.cnf
> [mysqld]
server-id=3>
> EOF
# diff my.cnf my.cnf.org
18,19d17
< [mysqld]
< server-id=3
#
步驟4: 重啓Master節點與Slave節點
- 重啓Master節點與Slave節點
liumiaocn:mysql liumiao$ docker-compose restart
Restarting mysql_slave1_1 ... done
Restarting mysql_master_1 ... done
Restarting mysql_slave2_1 ... done
liumiaocn:mysql liumiao$ docker-compose ps
Name Command State Ports
-----------------------------------------------------------------------------
mysql_master_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3306->3306/tcp
mysql_slave1_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3307->3306/tcp
mysql_slave2_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3308->3306/tcp
liumiaocn:mysql liumiao$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
38568ff39efd liumiaocn/mysql:5.7.16 "docker-entrypoint.s…" 18 minutes ago Up 6 seconds 0.0.0.0:3307->3306/tcp mysql_slave1_1
1fd3808076b2 liumiaocn/mysql:5.7.16 "docker-entrypoint.s…" 18 minutes ago Up 6 seconds 0.0.0.0:3306->3306/tcp mysql_master_1
1f6ae8f3384c liumiaocn/mysql:5.7.16 "docker-entrypoint.s…" 18 minutes ago Up 6 seconds 0.0.0.0:3308->3306/tcp mysql_slave2_1
liumiaocn:mysql liumiao$
- 確認狀態
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.16-log MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 | 154 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
mysql>
步驟5: 設定並啓動slave
設定Slave1
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3307
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.16 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show slave status;
Empty set (0.00 sec)
mysql>
mysql> change master to master_host='master',master_port=3306, master_user='replicationuser',master_password='replicationuser',master_log_file='mysql-bin.000001',master_log_pos=154;
Query OK, 0 rows affected, 2 warnings (0.03 sec)
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State:
Master_Host: master
Master_User: replicationuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 154
Relay_Log_File: 38568ff39efd-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: No
Slave_SQL_Running: No
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: 154
Relay_Log_Space: 154
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
Master_UUID:
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State:
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
ERROR:
No query specified
mysql>
注意此時Slave_IO_Running和Slave_SQL_Running均爲No
- 啓動slave1
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)
mysql>
- 確認狀態
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: master
Master_User: replicationuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 154
Relay_Log_File: 38568ff39efd-relay-bin.000003
Relay_Log_Pos: 367
Relay_Master_Log_File: mysql-bin.000002
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: 154
Relay_Log_Space: 747
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_UUID: 457caec2-a898-11ea-8e55-0242c0a83003
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
ERROR:
No query specified
mysql>
設定Slave2
Slave2與Slave1同樣的操作完整做一遍，唯一區別在於連接時指定的端口爲3308，執行日誌如下所示。
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3308
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.16 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show slave status;
Empty set (0.00 sec)
mysql> change master to master_host='master',master_port=3306, master_user='replicationuser',master_password='replicationuser',master_log_file='mysql-bin.000001',master_log_pos=154;
Query OK, 0 rows affected, 2 warnings (0.03 sec)
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State:
Master_Host: master
Master_User: replicationuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 154
Relay_Log_File: 1f6ae8f3384c-relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: No
Slave_SQL_Running: No
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: 154
Relay_Log_Space: 154
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
Master_UUID:
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State:
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
ERROR:
No query specified
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: master
Master_User: replicationuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 154
Relay_Log_File: 1f6ae8f3384c-relay-bin.000003
Relay_Log_Pos: 367
Relay_Master_Log_File: mysql-bin.000002
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: 154
Relay_Log_Space: 747
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_UUID: 457caec2-a898-11ea-8e55-0242c0a83003
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
ERROR:
No query specified
mysql>
結果確認
主從結構最重要的在於主寫從讀的複製功能，在Master庫中創建一個數據庫，在數據庫中建表，在表中插入數據庫，然後在從庫中確認數據庫、表和數據的內容，從而驗證上述一主兩從的MySQL是否能夠進行最基本的動作。
Master操作
- 建庫
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.16-log MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.00 sec)
mysql> create database testdb;
Query OK, 1 row affected (0.00 sec)
mysql>
- 建表
mysql> use testdb;
Database changed
mysql> create table person (id int not null, name varchar(20));
Query OK, 0 rows affected (0.02 sec)
mysql> desc person;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | | NULL | |
| name | varchar(20) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.01 sec)
mysql>
- 插入數據
mysql> insert into person values(1001,'liumiao');
Query OK, 1 row affected (0.01 sec)
mysql> select * from person;
+------+---------+
| id | name |
+------+---------+
| 1001 | liumiao |
+------+---------+
1 row in set (0.00 sec)
mysql>
Slave1節點確認
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3307
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.16 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testdb |
+--------------------+
5 rows in set (0.00 sec)
mysql> use testdb
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+------------------+
| Tables_in_testdb |
+------------------+
| person |
+------------------+
1 row in set (0.00 sec)
mysql> desc person;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | | NULL | |
| name | varchar(20) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
mysql> select * from person;
+------+---------+
| id | name |
+------+---------+
| 1001 | liumiao |
+------+---------+
1 row in set (0.00 sec)
mysql>
Slave 2節點確認
liumiaocn:mysql liumiao$ mysql -uroot -pliumiaocn -h127.0.0.1 -P3308
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.16 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
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.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testdb |
+--------------------+
5 rows in set (0.00 sec)
mysql> use testdb
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+------------------+
| Tables_in_testdb |
+------------------+
| person |
+------------------+
1 row in set (0.00 sec)
mysql> desc person
-> ;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | int(11) | NO | | NULL | |
| name | varchar(20) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
mysql> select * from person;
+------+---------+
| id | name |
+------+---------+
| 1001 | liumiao |
+------+---------+
1 row in set (0.00 sec)
mysql>
總結
本文爲了簡單說明主從的複製功能主要的使用方式，設定內容能夠滿足主寫從讀，在實際使用中需要進一步擴展和設定以滿足相應的需求。