主從同步構建思路:
確保數據相同--從庫必須要有主庫中的數據
主服務配置--啓用binlog日誌,授權用戶,查看正在使用的日誌
從服務器配置--設定server_id,指定主庫信息
測試配置--客戶端連接主數據庫,寫入數據,從庫上也能查詢
主服務器:host50 192.168.4.50
從服務器:host51 192.168.4.51
一,在主服務器host50上配置主服務器
*打開配置文件 vim /etc/my.cnf 修改如下:
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
[mysqld]
general-log
log-bin=master51 //啓用binlog日誌命名前綴master51
server_id=51 //指定服務器ID號
binlog_format="mixed" //指定日誌格式
plugin-load="rpl_semi_sync_master=semisync_master.so;rpl_semi_sync_slave=semisync_slave.so"
rpl_semi_sync_master-enabled = 1
rpl_semi_sync_slave-enabled = 1
/*高可用架構下。需要同時啓動master和slave
#validate_password_length=6
#validate_password_policy=0
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
[root@host50]# systemctl restart mysqld
[root@host50]#ls /var/lib/mysql/master50.*
[root@host50]#mysql -uroot -p123456
用戶授權:給從庫host51添加連接時使用的用戶名
mysql> grant replication slave on *.* to repluser@"192.168.4.51" identified by "123qqq...A";
查看正在使用的binlog日誌信息
mysql> show master status;
+-----------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-----------------+----------+--------------+------------------+-------------------+
| master51.000001 | 154 | | | |
+-----------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
*************************************************************************************************************************************
二,在host51中指定從庫信息
*打開配置文件 vim /etc/my.cnf 修改如下:
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
[mysqld]
server_id=51 //指定服務器ID號
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
[root@host51]# systemctl restart mysqld
進入數據庫
[root@host50]#mysql -uroot -p123456
指定主庫信息
mysql>change master to
>master_user="repluser", //主庫授權用戶名
>master_host="192.168.4.50", //指定主庫IP地址
>master_password="123qqq...A", //授權用戶名密碼
>master_log_file="master51.000001", //日誌文件
>master_log_pos=154; //偏移位置
mysql>start slave; //啓動slave進程
mysql>show slave status\G //查看slave狀態
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.4.50
Master_User: repluser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: master51.000001
Read_Master_Log_Pos: 599
Relay_Log_File: host52-relay-bin.000005
Relay_Log_Pos: 810
Relay_Master_Log_File: master51.000002
Slave_IO_Running: Yes //IO線程已運行
Slave_SQL_Running: Yes //SQL線程已運行
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: 599
Relay_Log_Space: 1183
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: 51
Master_UUID: 7663861b-8be3-11e8-b256-5254001db4c8
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)
三,測試配置
在主庫上操作數據:
-新建newdb庫t1表
-任意插入幾條表記錄
在從庫上查看數據更改情況
-確認新建的newdb庫t1表
-列出t1表的所有記錄
*******************************************************************************************************************************************
配置主從同步可能出現的問題
問題一:
Slave_IO 線程沒有運行
---報錯:Slave_IO_Running:NO
mysql>show slave status\G
Slave_IO_Running:NO
Last_IO_Error: 報錯信息......
原因分析
----連接不上master數據庫服務器
解決辦法:
---檢查物理連接(ping) 檢查授權用戶
---禁用防火牆 關閉SElinux
---binlog日誌文件指定錯誤(日誌名或pos節點)
mysql> stop slave
mysql>change master to 選項=值;
mysql>start slave;
問題二:
Slave_SQL 線程沒有運行
---報錯:Slave_SQL_Running:NO
mysql>show slave status\G
Slave_SQL_Running:NO
Last_SQL_Error: 報錯信息......
原因分析
----執行本機中繼日誌裏的sql命令時,sql命令使用的庫,表或記錄在本機並不存在
解決辦法:
mysql> stop slave;
mysal>...... //創建或恢復需要用到的庫或者表
mysql> start slave;