4.1 環境介紹
4.1.1 Master環境介紹
1)操作系統:centos7
2)Mysql版本:5.7.23
3)IP:10.0.0.31
4.1.2 Slave環境介紹:
1)操作系統:centos7
2)Mysql版本:5.7.23
3)IP:10.0.0.32
4.2 配置
4.2.1 Master配置
1)my.cnf配置
#vim /etc/my.cnf
[root@ok_1 ~]# vim /etc/my.cnf
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
## replication
server_id=31
binlog-ignore-db=mysql
log-bin=master-mysql-bin
binlog_cache_size=1M
binlog_format=mixed
expire_logs_days=30
2)重啓mysql
[root@ok_1 ~]# systemctl restart mysqld
3)在主服務器上建立帳戶並授權slave
[root@ok_1 ~]# mysql -uroot -p
mysql> set global validate_password_policy=0;
Query OK, 0 rows affected (0.00 sec)
mysql> set global validate_password_length=1;
Query OK, 0 rows affected (0.00 sec)
這裏要寫這兩句畫的原因是mysql5.7不允許寫簡單密碼,所以這裏要通過命令更改mysql配置文件使其支持簡單密碼。
mysql> GRANT REPLICATION SLAVE ON *.* to 'mysqlsync'@'%' identified by '123456';
Query OK, 0 rows affected, 1 warning (0.00 sec)
//這裏
//這裏也不用寫Slave端的用戶名,因爲這裏的mysql用戶名是專門用來做複製的!
//一般不用root帳號,“%”表示所有客戶端都可能連,只要帳號,密碼正確,此處可用具體客戶端IP代替,如192.168.8.1,加強安全。
//"mysqlsync"也不用寫Slave端的用戶名,因爲這裏是mysql專門用來做複製的!
4) 登錄mysql,查詢master的狀態
mysql> FLUSH TABLES WITH READ LOCK;
Query OK, 0 rows affected (0.01 sec)
##把數據表先鎖住,不讓Position 變化!
mysql> show master status;
+-------------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-------------------------+----------+--------------+------------------+-------------------+
| master-mysql-bin.000001 | 434 | | mysql | |
+-------------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
注:執行完此步驟後不要再操作主服務器MYSQL,防止主服務器狀態值變化。
4.2.2 Slave配置
1)my.cnf配置
[root@0k_2 ~]# vim /etc/my.cnf
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
## replication
server_id=32
binlog-ignore-db=mysql
log-bin=mysql-slave-bin
binlog_cache_size = 1M
binlog_format=mixed ##mixed是開啓混合同步模式
expire_logs_days=30
relay_log=mysql-relay-bin
log_slave_updates=1
read_only=1
2)重啓mysql
[root@0k_2 ~]# systemctl restart mysqld
3)配置從服務器Slave:
[root@0k_2 ~]# mysql -uroot -p
mysql> change master to
-> master_host='10.0.0.31',
-> master_user='mysqlsync',
-> master_password='123456',
-> master_port=3306,
-> master_log_file='master-mysql-bin.000001',
-> master_log_pos=434,
-> master_connect_retry=30;
Query OK, 0 rows affected, 2 warnings (0.12 sec)
//注意不要斷開,“434”無單引號,master_host的地址一定不能寫錯!
mysql> start slave; #啓動從服務器複製功能
Query OK, 0 rows affected (0.00 sec)
回到Master端,解鎖數據表
mysql> unlock tables;
Query OK, 0 rows affected (0.00 sec)
- 回到從服務器檢查從服務器複製功能狀態:
mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.0.31
Master_User: mysqlsync
Master_Port: 3306
Connect_Retry: 30
Master_Log_File: master-mysql-bin.000001
Read_Master_Log_Pos: 434
Relay_Log_File: mysql-relay-bin.000002
Relay_Log_Pos: 327
Relay_Master_Log_File: master-mysql-bin.000001
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: 434
Relay_Log_Space: 534
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: 31
Master_UUID: 19a7156d-213a-11e9-b107-5254004efc34
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 (0.01 sec)
特別注意:Slave_IO及Slave_SQL進程必須正常運行,即YES狀態,否則都是錯誤的狀態。
5)開始驗證
在master機器上查看狀態,可以看見slave的連接信息
mysql> show processlist\G;
*************************** 1. row ***************************
Id: 2
User: root
Host: localhost
db: NULL
Command: Query
Time: 0
State: starting
Info: show processlist
*************************** 2. row ***************************
Id: 3
User: mysqlsync
Host: 10.0.0.32:52842
db: NULL
Command: Binlog Dump
Time: 313
State: Master has sent all binlog to slave; waiting for more updates
Info: NULL
2 rows in set (0.00 sec)
在slave機器上查看狀態,可以看見master的連接信息
mysql> show processlist\G;
*************************** 1. row ***************************
Id: 2
User: root
Host: localhost
db: NULL
Command: Query
Time: 0
State: starting
Info: show processlist
*************************** 2. row ***************************
Id: 3
User: system user
Host:
db: NULL
Command: Connect
Time: 376
State: Waiting for master to send event
Info: NULL
*************************** 3. row ***************************
Id: 4
User: system user
Host:
db: NULL
Command: Connect
Time: 376
State: Slave has read all relay log; waiting for more updates
Info: NULL
3 rows in set (0.00 sec)
(1)初始狀態
(2)新建test表
(3)驗證結果
成功!!
如果出現
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
但是mysql主從依然不能同步數據時
解決方案:
salve從庫端:
#停止slave服務
mysql> stop slave;
#跳過一步錯誤,後面的數字可變,如果還不行可執行多次
mysql> set global sql_slave_skip_counter =1;
#開始slave服務
mysql> start slave;
#查看slave狀態
mysql> show slave status\G
備註:
此方法的前提條件是主從端mysql的數據是一模一樣的起始數據庫內容(表、字段、內部值都必須一樣!)
這種同步方式並不是實時同步。會有滯後甚至slave端數據丟失的情況出現。在高併發的生產環境下不建議使用!!!!
此方法的價值在於便於理解主從複製的原理!!!