Mysql必读详解MySQL主从复制实战 - 基于日志点的复制
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《Mysql必读详解MySQL主从复制实战 - 基于日志点的复制》要点： MYSQL实例基于日志点的复制 MYSQL实例1、在主库与从库上建立专用的复制账号 MYSQL实例
MariaDB [employees]> create user 'repl'@'172.%' identified by '123456';
MYSQL实例注意在生产上的密码必须依照相关规范以达到一定的密码强度,并且规定在从库上的特定网段上才能访问主库 MYSQL实例2、在主库与从库上授予复制权限 MYSQL实例
MariaDB [employees]> grant replication slave on *.* to 'repl'@'172.%';
MYSQL实例3、配置主库 MYSQL实例注意启用二进制日志需要重启服务,而server_id是一个动态参数,可以结合命令行与配置文件以达到免重启的持久化配置. 注意server_id在集群中是唯一的. MYSQL实例
[mysqld]
log_bin = /var/log/mysql/mariadb-bin
log_bin_index = /var/log/mysql/mariadb-bin.index
binlog_format = row
server_id = 101
MYSQL实例NOTE: 把日志与数据分开是个好习惯,最好能放到不同的数据分区 MYSQL实例4、配置从库 MYSQL实例选项log_slave_update决定是否把中继日志relay_log存放到本机的binlog中,如果是配置链路复制,那么该选项必填. 注意server_id在集群中是唯一的. MYSQL实例
[mysqld]
# replication
log_bin = /var/log/mysql/mariadb-bin
log_bin_index = /var/log/mysql/mariadb-bin.index
server_id = 102
# slaves
relay_log = /var/log/mysql/relay-bin
relay_log_index = /var/log/mysql/relay-bin.index
relay_log_info_file = /var/log/mysql/relay-bin.info
log_slave_updates = ON
read_only
MYSQL实例5、初始化从库的数据 MYSQL实例此处使用mysqldump在主库上进行备份,在生产上建议大家用xtrabackup进行无锁的热备(基于innodb引擎). MYSQL实例备份主库上的employees数据库的数据 代码如下:mysqldump --single-transaction --master-data=1 --triggers --routines --databases employees -u root -p >> backup.sql MYSQL实例将备份文件backup.sql通过scp或者docker volume卷挂载到从服务器上,并且导入至从库中 MYSQL实例
mysql -u root -p < backup.sql
MYSQL实例6、启动复制链路 MYSQL实例现有master@172.20.0.2和slave@172.20.0.3,并且已经通过mysqldump将数据同步至从库slave中. 现在在从服务器slave上配置复制链路 MYSQL实例
MariaDB [(none)]> CHANGE MASTER TO MASTER_HOST='master',MASTER_USER='repl',MASTER_PASSWORD='123456',MASTER_LOG_FILE='mariadb-bin.000029',MASTER_LOG_POS=516;
Query OK,0 rows affected (0.02 sec)
MYSQL实例在从库上启动复制链路 MYSQL实例
MariaDB [(none)]> start slave;
Query OK,0 rows affected (0.01 sec)
MYSQL实例7、在从库上检查slave状态 MYSQL实例Slave_IO_Running与Slave_SQL_Running必须为YES,如果出现错误须详细阅读Last_IO_Error或Last_SQL_Error的提示信息 MYSQL实例
MariaDB [(none)]> show slave statusG
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: master
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mariadb-bin.000029
Read_Master_Log_Pos: 516
Relay_Log_File: relay-bin.000002
Relay_Log_Pos: 539
Relay_Master_Log_File: mariadb-bin.000029
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: 516
Relay_Log_Space: 831
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: 101
Master_SSL_Crl:
Master_SSL_Crlpath:
Using_Gtid: No
Gtid_IO_Pos:
Replicate_Do_Domain_Ids:
Replicate_Ignore_Domain_Ids:
Parallel_Mode: conservative
1 row in set (0.00 sec)
MYSQL实例8、在主库检查dump线程 MYSQL实例检测是否已经正确启动binlog dump线程 MYSQL实例
MariaDB [(none)]> show processlist G
*************************** 1. row ***************************
Id: 7
User: root
Host: 172.20.0.1:41868
db: employees
Command: Sleep
Time: 56
State:
Info: NULL
Progress: 0.000
*************************** 2. row ***************************
Id: 10
User: repl
Host: 172.20.0.3:45974
db: NULL
Command: Binlog Dump
Time: 246
State: Master has sent all binlog to slave; waiting for binlog to be updated
Info: NULL
Progress: 0.000
MYSQL实例可以看到row 2上有Command为Binlog Dump的命令被启动,证明复制线程已经被成功启动 MYSQL实例9、总结 MYSQL实例优点
MYSQL实例缺点
MYSQL实例在一主多从环境下,若旧master宕机后在集群中选举出新master,其他的从库要对这个新的master进行重新同步,由于每个DB的binlog都是独立存在,所以很难找出开始同步的日志点 MYSQL实例以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持编程之家PHP. （编辑：李大同） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |