MySQL的主从、半主从、主主复制配置详细
实验拓扑图模型:
############################【实验MySQL服务器的主从复制:】#######################################
###########################修改主配置文件########################################## [root@director2 ~ ]#vim /etc/mysql/my.cnf [mysqld] 42 thread_concurrency= 8 43 innodb_file_per_table = on 44 datadir = /mydata ###############库目录 45 skip_name_resolve = on ###############不反解主机名 59 log-bin=mysql-bin ###############启用二进制日志 67 server-id = 1 ###############唯一ID
[root@director2 ~ ]# chkconfig --list mysqld #####保证mysqld的开启自启动 mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off
############################授权一个有复制权限的用户##############################################
mysql> grant replication client,replication slave on *.* to 'cpuser'@'172.16.249.106' identified by "magedu"; Query OK, 0 rows affected (0.08 sec) mysql> flush privileges; Query OK, 0 rows affected (0.01 sec)
###########################从节点准备#############################################################
[root@node2 ~ ]# groupadd -g 306 mysql [root@node2 ~ ]# useradd -g 306 -u 306 mysql [root@node2 ~ ]# mkdir /mydata [root@node2 ~ ]# cd /mydata/ [root@node2 / ]# chown -R mysql:mysql /mydata/ [root@node2 / ]# chmod -R a+w /mydata/
###################主节点:把mysql文件传输给主节点################################################
[root@node2 mysql ]#id mysql uid=306(mysql) gid=306(mysql) groups=306(mysql) [root@node2 mysql ]#ll /mydata total 0 [root@node2 mysql ]#ll -d /mydata drwxrwxrwx 2 mysql mysql 4096 Jan 23 11:03 /mydata [root@node2 mysql ]#mkdir /etc/mysql [root@node2 mysql ]# scripts/mysql_install_db --user=mysql --datadir=/mydata ###初始化 [root@director2 ~ ]# scp /etc/mysql/my.cnf 172.16.249.106:/etc/mysql/ ###把主节点的配置文件拷贝过来 [root@node2 / ]# vim /etc/mysql/my.cnf ####编辑从节点的配置文件 59 #log-bin=mysql-bin ####从节点不启用二禁止日志 67 server-id = 20 ####server-id保持唯一 68 relay-log = relay-bin ####从节点开启中继日志 69 read-only =on ####只读模式开启(注意:这个只能限制普通用户)
方法二:此处也可以直接施加读锁。在mysql> lock tables testdb read;
mysql> show variables like 'relay%'; #####中继日志开启了 +-----------------------+--------------------+ | Variable_name | Value | +-----------------------+--------------------+ | relay_log | relay-bin | | relay_log_index | | | relay_log_info_file | relay-log.info | | relay_log_purge | ON | | relay_log_recovery | OFF | | relay_log_space_limit | 0 | +-----------------------+--------------------+ mysql> show variables like "read%"; #############只读模式开启 +----------------------+---------------------+ | Variable_name | Value | +----------------------+---------------------+ | read_buffer_size | 1048576 | | read_only | ON | | read_rnd_buffer_size | 4194304 | +----------------------+---------------------+
#############################至此主从各单个节点配置结束########################################
#############################配置从连接主#######################################################
#####主节点查看二进制文件的存储位置
mysql> show master status; +------------------+----------+--------------+------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | | +------------------+----------+--------------+------------------+ | mysql-bin.000003 | 501 | | | +------------------+----------+--------------+------------------+ 1 row in set (0.04 sec) ######################################建立主从连接####################################### mysql> change master to master_host='172.16.249.122',master_user='cpuser',master_password='magedu',master_log_file='mysql-bin.000003',master_log_pos=501;
mysql> show slave status\G; #####查看当前从节点状态 ***************************1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host:172.16.249.122 Master_User: cpuser Master_Port: 3306 Connect_Retry: 60 Master_Log_File:mysql-bin.000003 Read_Master_Log_Pos:501 Relay_Log_File: relay-bin.000002 Relay_Log_Pos: 529 Relay_Master_Log_File: mysql-bin.000003 Slave_IO_Running: Yes ###IO线程启用 Slave_SQL_Running: Yes ###SQL线程已经启用
#############################################测试结果##############################################
######主节点创建库
mysql> create database testdb; Query OK, 1 row affected (0.03 sec) mysql> use testdb; Database changed
此时从节点已经同步了:
############################################创建一个表############################################
mysql> create table students(id tinyint unsigned not null auto_increment unique key); Query OK, 0 rows affected (0.25 sec)
总结步骤:::
【主服务器】
1,主服务器的server-id,保持唯一。
2,开启二进制日志。
3,授权一个可以复制的用户,最小权限使用,指向从服务器最好。
【从服务器】
1,关闭二进制日志,开启中继日志
2,保持唯一的server-id
3,为了防止从服务器写入数据,开启只读模式。
4,连接主服务器,指定主服务器Ip,授权的用户,密码,上一次的二进制文件的位置。
5,开启IO,SQL线程。
########################################【半主从模式】########################################
##############此处的半主从是在主从的基础上的半同步:
1,条件是有一个从服务器,他和主服务器同样的写同步,如果同步超时,把这个从这个从节点降级为异步。恢复正常的状态。
【完成半同步,需要的是步骤是各自的插件】
[root@node2 plugin]# pwd /usr/local/mysql/lib/plugin [root@node2 plugin ]# semisync_master.so(主节点的插件) semisync_slave.so (从节点的插)
主节点:安装插件
此时全局参数变多了
mysql> install plugin rpl_semi_sync_master soname 'semisync_master.so'; Query OK, 0 rows affected (0.15 sec) mysql> show global variables like '%semi%'; #####安装好了之后,生成很多变量 +------------------------------------+---------------------+ | Variable_name | Value | +------------------------------------+---------------------+ | rpl_semi_sync_master_enabled | OFF | 表示虽然安装,但是没有启用 | rpl_semi_sync_master_timeout | 10000 | ###探测主的超时时长 | rpl_semi_sync_master_trace_level | 32 | ####追踪级别 | rpl_semi_sync_master_wait_no_slave | ON | ####等待从服务器的上线的时间 +------------------------------------+---------------------+ mysql> set global rpl_semi_sync_master_enabled=1; #####启用这个插件 Query OK, 0 rows affected (0.00 sec) mysql> set global rpl_semi_sync_master_timeout=2000; Query OK, 0 rows affected (0.00 sec)
【从节点安装插件配置】
mysql> install plugin rpl_semi_sync_slave soname 'semisync_slave.so'; Query OK, 0 rows affected (0.10 sec) mysql> show global variables like '%semi%'; +---------------------------------+-------------------+ |Variable_name | Value | +---------------------------------+-------------------+ | rpl_semi_sync_slave_enabled | OFF | ###插件未启用 | rpl_semi_sync_slave_trace_level | 32 | +---------------------------------+-------------------+ mysql> set global rpl_semi_sync_slave_enabled=1; ####启用插件 Query OK, 0 rows affected (0.00 sec)
###############################至此两个节点的插件全部安装,启用完毕###############################
mysql> show global status like '%semi%'; +--------------------------------------------+-----------------------------+ |Variable_name | Value | +--------------------------------------------+-----------------------------+ | Rpl_semi_sync_master_clients | 0 | | Rpl_semi_sync_master_net_avg_wait_time | 0 | | Rpl_semi_sync_master_net_wait_time | 0 | | Rpl_semi_sync_master_net_waits | 0 | | Rpl_semi_sync_master_no_times | 0 | | Rpl_semi_sync_master_no_tx | 0 | | Rpl_semi_sync_master_status | ON | | Rpl_semi_sync_master_timefunc_failures | 0 | | Rpl_semi_sync_master_tx_avg_wait_time | 0 | | Rpl_semi_sync_master_tx_wait_time | 0 | | Rpl_semi_sync_master_tx_waits | 0 | | Rpl_semi_sync_master_wait_pos_backtraverse | 0 | | Rpl_semi_sync_master_wait_sessions | 0 | | Rpl_semi_sync_master_yes_tx | 0 | +--------------------------------------------+-----------------------------+ mysql> stop slave IO_THREAD; Query OK, 0 rows affected (0.00 sec) mysql> start slave IO_THREAD; Query OK, 0 rows affected (0.00 sec)
再次查看已经启用了。下面直接测试使用即可######
##################################【实验二双主模式的实现】######################################
#################还是用的之前两台主机,重新初始化重新配置
1,双节点各自使用不同的server id
2, 都启用binlog 和relay log
3,自动自动增长的id字段的增长特殊定义:
3, 都授权有复制权限的用户账号
修改节点一的配置文件
节点一:配置文件
[root@director2 ~ ]#vim .my.cnf 59 log-bin=mysql-bin ####开启二进制日志 67 server-id = 10 ####服务器唯一ID 68 relay-log=relay-bin ####开启中继日志,因为互为主从 69 auto_increment_offset=1 ####指定日志的初始偏移量 70 auto_increment_increment=2 ####每次的偏移步长 [root@director2 bin ]# mysql mysql> grant replication slave,replication client on *.* to 'cpuser'@'%' identified by 'magedu';Query OK, 0 rows affected (0.04 sec) ####给节点授权一个可链接用户 mysql> flush privileges; mysql> show master status; +------------------+----------+--------------+------------------------------------+ |File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+----------+--------------+------------------------------------+ |mysql-bin.000003 | 1796 | | | +------------------+----------+--------------+------------------------------------+ mysql> change master to master_host='172.16.249.106',master_user='cpuser',master_password='magedu',master_log_file='mysql-bin.000001',master_log_pos=493; Query OK, 0 rows affected (0.10 sec) mysql> start slave;
【节点二的配置文件】
59 log-bin=mysql-bin ####开启二进制日志 67 server-id = 20 ####区别节点一的ID 68 relay-log = relay-bin ####开启中继日志(也有从的角色) 69 auto-increment_offset =2 ####自增其实位置 70 auto-increment_increment=2 ####自增的步长 [root@node2 mysql ]# mysql mysql> grant replication slave,replication client on *.* to 'cpuser'@'%' identified by'magedu'; mysql> flush privileges; mysql> change master to mysql> show master status; +------------------+----------+--------------+-------------------------------+ |File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+----------+--------------+-------------------------------+ |mysql-bin.000001 | 493 | | | +------------------+----------+--------------+-------------------------------+ master_host='172.16.249.122',master_user='cpuser',master_password='magedu',master_log_file='mysql-bin.000003',master_log_pos=1796; Query OK, 0 rows affected (0.07 sec) mysql> start slave;
##################节点一创建数据库tb1
##################节点二可以立即同步
##################节点二:在这个库里面创建表
##################并且插入数据1
##################节点一,已经同步
至此双主模式模式也实现完毕!!!!!!!!!!!!!