Mysql主从复制(详细)
环境搭建
环境信息:
- master
- ip:192.168.188.99
- Mysql版本:5.6.45
- 服务器版本:CentOS7
- slave
- ip:192.168.188.102
- Mysql版本:5.6.45
- 服务器版本:CentOS7
配置Mysql
master
在[mysqld]下添加：
#启用二进制日志
log-bin=mysql-bin
#服务器唯一ID，一般取IP最后一段
server-id=99
Master完整配置
[root@master ~]# cat /etc/my.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.6/en/server-configuration-defaults.html
[mysqld]
# 启用二进制日志
log-bin=mysql-bin
# 服务器的唯一id,一般选取ip地址最后一段
server-id=99
#
# 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
#
# 永久开启慢查询
slow_query_log = ON
slow_query_log_file = /var/log/mysql/slow.log
long_query_time = 1
# 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
# 不区分大小写
# lower_case_table_names = 1
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Recommended in standard MySQL setup
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
Slave 配置
仅仅配置这一条就够了,不过一定要注意查看配置是否生效
# 服务器的唯一id,一般选取ip地址最后一段
server-id=102
slave完整配置信息
[root@slave etc]# cat /etc/my.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.6/en/server-configuration-defaults.html
[mysqld]
# 启用二进制日志
#log-bin=mysql-bin
# 服务器的唯一id,一般选取ip地址最后一段
server-id=102
#
# 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
#
# 永久开启慢查询
slow_query_log = ON
slow_query_log_file = /var/log/mysql/slow.log
long_query_time = 1
# 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
# 不区分大小写
# lower_case_table_names = 1
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Recommended in standard MySQL setup
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
两台主机(Master和Slave)修改完配置文件之后务必要重启下Mysql
service mysqld restart
Server-id核对
重启完之后登录查看master的server-id是否和mysql.cnf文件中一致
mysql> SHOW VARIABLES LIKE '%server_id%';
+----------------+-------+
| Variable_name | Value |
+----------------+-------+
| server_id | 99 |
| server_id_bits | 32 |
+----------------+-------+
2 rows in set (0.00 sec)
重启完之后登录查看slave的server-id是否和mysql.cnf文件中一致
mysql> SHOW VARIABLES LIKE '%server_id%';
+----------------+-------+
| Variable_name | Value |
+----------------+-------+
| server_id | 102 |
| server_id_bits | 32 |
+----------------+-------+
2 rows in set (0.00 sec)
Master创建同步账户
主机创建一个新的slave用户，设置复制权限
-
创建用户
create user 'slave'@'从机IP' identified by 'root'; -
设置权限
grant replication slave on *.* to 'slave'@'从机IP' identified by 'root';
最后刷新权限信息
FLUSH PRIVILEGES;
查看Master状态
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000006 | 346 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
Slave开启配置同步
登录到slave服务器中执行
CHANGE MASTER TO
-- Master的地址
MASTER_HOST='192.168.188.99',
-- Master的端口号
MASTER_PORT=3306,
-- Master中刚刚创建的slave用户
MASTER_USER='slave',
-- Master的刚刚创建的slave用户的密码
MASTER_PASSWORD='root',
-- 上面使用show master status查出来的字段File
MASTER_LOG_FILE='mysql-bin.000006',
-- 上面使用show master status查出来的字段Position
MASTER_LOG_POS=120;
注意语句中间不要断开，master_port为mysql服务器端口号(无引号)，master_user为执行同步操作的数据库账户，“120”无单引号(此处的120就是show master status 中看到的position的值，这里的mysql-bin.000006就是file对应的值)。
Slave启动服务器复制功能
登录到slave服务器中执行
start slave
检查从服务器复制功能的状态
show slave status
Slave_IO_State Master_Host Master_User Master_Port Connect_Retry Master_Log_File Read_Master_Log_Pos Relay_Log_File Relay_Log_Pos Relay_Master_Log_File Slave_IO_Running Slave_SQL_Running Replicate_Do_DB Replicate_Ignore_DB Replicate_Do_Table Replicate_Ignore_Table Replicate_Wild_Do_Table Replicate_Wild_Ignore_Table Last_Errno Last_Error Skip_Counter Exec_Master_Log_Pos Relay_Log_Space Until_Condition Until_Log_File Until_Log_Pos Master_SSL_Allowed Master_SSL_CA_File Master_SSL_CA_Path Master_SSL_Cert Master_SSL_Cipher Master_SSL_Key Seconds_Behind_Master Master_SSL_Verify_Server_Cert Last_IO_Errno Last_IO_Error Last_SQL_Errno Last_SQL_Error Replicate_Ignore_Server_Ids Master_Server_Id Master_UUID Master_Info_File SQL_Delay SQL_Remaining_Delay Slave_SQL_Running_State Master_Retry_Count Master_Bind Last_IO_Error_Timestamp Last_SQL_Error_Timestamp Master_SSL_Crl Master_SSL_Crlpath Retrieved_Gtid_Set Executed_Gtid_Set Auto_Position
-------------------------------- -------------- ----------- ----------- ------------- ---------------- ------------------- ----------------------- ------------- --------------------- ---------------- ----------------- --------------- ------------------- ------------------ ---------------------- ----------------------- --------------------------- ---------- ---------- ------------ ------------------- --------------- --------------- -------------- ------------- ------------------ ------------------ ------------------ --------------- ----------------- -------------- --------------------- ----------------------------- ------------- ------------- -------------- -------------- --------------------------- ---------------- ------------------------------------ -------------------------- --------- ------------------- --------------------------------------------------------------------------- ------------------ ----------- ----------------------- ------------------------ -------------- ------------------ ------------------ ----------------- ---------------
Waiting for master to send event 192.168.188.99 slave 3306 60 mysql-bin.000006 346 mysqld-relay-bin.000002 509 mysql-bin.000006 Yes Yes 0 0 346 683 None 0 No 0 No 0 0 99 32c5596d-bf2f-11e9-818a-000c298b2a3c /var/lib/mysql/master.info 0 (NULL) Slave has read all relay log; waiting for the slave I/O thread to update it 86400 0
Slave_IO_Running及Slave_SQL_Running进程必须正常运行，即YES状态，否则都是错误的状态(如：其中一个NO均属错误)。
测试主从同步
前提,有相同的数据库,有相同的数据.
错误分析
错误代码： 1794
描述:SLAVE IS NOT configured OR failed TO initialize properly. You must AT LEAST SET --server-id TO ENABLE either a MASTER OR a slave. Additional error messages can be FOUND IN the MySQL error log.
遇到这种错误一定要在Master和Slave两个不同机器上使用
**SHOW VARIABLES LIKE '%server_id%';**
命令查看自己的server_id和mysql.cnf文件中配置的是否一致.
这是个巨大的坑啊
End.