Docker下实现MySQL主从同步
本文是以最少步骤的安装,仅实现了在docker下mysql的主从同步
创建Docker镜像
创建两个MySQL版本:5.7的镜像,一个容器名称为master,另一个为slaver
docker run -d --name master -e MYSQL_ROOT_PASSWORD=root -p 3306:3306 mysql:5.7
docker run -d --link master:master --name slaver -e MYSQL_ROOT_PASSWORD=root -p 3307:3306 mysql:5.7
通过docker inspect命令查看容器的ip
master 主数据库 172.17.0.2 3306
slaver 从数据库 172.17.0.3 3307 对宿主机是3306,对于容器来说依旧是3306
主数据库配置
修改配置主数据库master的配置文件
可以通过exec进入命令,但是需要更新apt-get,然后再安装vim编辑工具,所以我才用的是docker cp命令进行修改的
docker cp master:/etc/mysql/mysql.cnf D:/
将配置文件复制到D盘下,然后添加如下内容
[mysqld]
server-id=1
log-bin=log
binlog-ignore-db=mysql
binlog-ignore-db=information_schema
binlog-ignore-db=performance_schema
binlog-ignore-db=sys
#binlog-ignore-db设置不需要同步的库
然后再复制回去
docker cp D:/mysql.cnf master:/etc/mysql/
然后连接数据库执行一下命令
create user 'slaver'@'%' identified by 'slaver';
grant FILe on *.* to 'slaver'@'172.17.0.3' identified by 'slaver';
grant replication slave on *.* to 'slaver'@'172.17.0.3' identified by 'slaver';
flush privileges;
表示创建一个名为slaver密码也为slaver的账户,然后授予主从复制权限给这个用户,其中[172.17.0.3]为slaver的host
然后重启数据库(重启镜像)
连接主数据库master,执行show master status
mysql> show master status;
+------------+----------+--------------+-------------------------------------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------+----------+--------------+-------------------------------------------------+-------------------+
| log.000002 | 414 | | mysql,information_schema,performance_schema,sys | |
+------------+----------+--------------+-------------------------------------------------+-------------------+
1 row in set (0.00 sec)
在这里请记住 FIle 和 positon这两个值,在配置从数据库的时候需要指定这个
从数据库配置
修改从数据库配置
docker cp slaver:/etc/mysql/mysql.cnf D:/
将配置文件复制到D盘下,然后添加如下内容
[mysqld]
server-id=2
log-bin=mysql-bin
replicate-ignore-db=mysql
replicate-ignore-db=information_schema
replicate-ignore-db=performance_schema
replicate-ignore-db=sys
log-slave-updates
slave-skip-errors=all
slave-net-timeout=60
#binlog-ignore-db设置不需要同步的库
然后再复制回去
docker cp D:/mysql.cnf slaver:/etc/mysql/
然后重启数据库(重启镜像)
连接从数据库执行 stop slave
stop slave
change master to
MASTER_HOST ='10.20.66.150',
MASTER_USER ='slaver',
MASTER_PASSWORD ='slaver',
MASTER_PORT = 3306,
MASTER_LOG_FILE ='log.000002',
MASTER_LOG_POS =414;
start slave;
看到别人的博客在配置这里的地方都有错误,在这里我贴出官网文档, https://dev.mysql.com/doc/refman/5.7/en/change-master-to.html
到目前为止主从同步已经搭建完成，在从库中使用show slave status \G;查看同步状态
mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 172.17.0.2
Master_User: slaver
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: log.000002
Read_Master_Log_Pos: 414
Relay_Log_File: 3a03e76858dd-relay-bin.000003
Relay_Log_Pos: 615
Relay_Master_Log_File: log.000002
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB: mysql,information_schema,performance_schema,sys
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: 414
Relay_Log_Space: 1661
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: beecd22a-ac7b-11ea-b4ba-0242ac110002
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)
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
表示运行正常,如果失败,请看
Last_IO_Errno:
Last_IO_Error:
搭建过程中遇到了一个问题就是数据库密码错误导致无法连接主库,所以还是要仔细小心
具体的学习主从复制的配置,可以翻阅官方文档 Chapter 16 Replication
系统性的学习最好还是从官网文档开始