# Master Slave Replication

Master Slave Replication in windows, across two different MySQL versions(5.7.31 and 8.0.22)

## Getting Started

## Prerequisites

Download mysql-8.0.22-winx64.zip and mysql-5.7.31-winx64.zip from -

https://dev.mysql.com/downloads/mysql/

## Configuring ans initilizing the servers

### Configuring options file-

For master as-

[mysqld]	//for group mysqld
server-id=1	//set server-id 1
basedir=D:\\111111\\Softwares\\sql\\mysql-5.7.31-winx64\\mysql-5.7.31-winx64	\\directory of mysql extracted zip
datadir=D:\\111111\\Softwares\\sql\\mysql-5.7.31-winx64\\mysql-5.7.31-winx64\\data	\\directory where all the data of server is to be strore
log-bin=mysql-bin.log	//location of log dump and also enables binary loggin
innodb_flush_log_at_trx_commit  = 1
sync_binlog                 = 1	//enables sync of bin log
binlog-format               = ROW

For slave as-

[mysqld]
server-id=2	//different server id than master version
port=3307	//different port than master as both are running on same ip i.e. 127.0.0.1
basedir=D:\\111111\\Softwares\\sql\\mysql-8.0.22-winx64\\mysql-8.0.22-winx64	\\directory of extracted zip
datadir=D:\\111111\\Softwares\\sql\\mysql-8.0.22-winx64\\mysql-8.0.22-winx64\\data	\\directory where all the data is to be stored
skip-log-bin	\\disables binary logging

### Initializing database

mysqld.exe --defaults-file="basedir_master\my.ini.txt" --initialize --console
mysqld.exe --defaults-file="basedir_slave\my.ini.txt" --initialize --console

### Start servers and logging in

##### Start servers-

mysqld.exe --defaults-file="basedir_master\my.ini.txt" --console
mysqld.exe --defaults-file="basedir_slave\my.ini.txt" --console

--initialize : initializes database directory
--console : outputs logs in terminal

##### Login

mysql.exe --port=3306 -u root -p
mysql.exe --port=3307 -u root -p

## Configurin master-slave

Create a new user for replication:

mysql> CREATE USER 'replication'@'%' IDENTIFIED BY 'replication';
mysql> GRANT REPLICATION SLAVE ON *.* TO 'replication'@'%';

From basedir_master/bin:

mysqldump.exe -u root -p --ignore-table=mysql.innodb_index_stats --ignore-table=mysql.innodb_table_stats --all-databases --master-data=2 > replicationdump.sql

Check replicationdump.sql for line-

-- CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000003', MASTER_LOG_POS=609;

Import the dump you created in the previous step into the slave instance:

mysql -uroot -p --host=127.0.0.1 --port=3307 < replicationdump.sql

Connect to the slave instance using the MySQL client with the appropriate host and port:

mysql -uroot -p --host=127.0.0.1 --port=3307

Update the master information in slave server (take the replication coordinates from the dump file replicationdump.sql, as explained above):

mysql> CHANGE MASTER TO MASTER_HOST='127.0.0.1', MASTER_USER='replication', MASTER_PASSWORD='replication', MASTER_LOG_FILE='mysql-bin.000003', MASTER_LOG_POS=609;

Start the slave:

mysql> START SLAVE;

Check status:

mysql>SHOW SLAVE STATUS \G

If you get the following output, replication was successful:

*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 127.0.0.1
                  Master_User: replication
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000003
          Read_Master_Log_Pos: 1800
               Relay_Log_File: DESKTOP-1U6PSDP-relay-bin.000002
                Relay_Log_Pos: 1513
        Relay_Master_Log_File: mysql-bin.000003
             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: 1800
              Relay_Log_Space: 1732
              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: 1
                  Master_UUID: 4d488924-1ff9-11eb-968c-9828a610e132
             Master_Info_File: mysql.slave_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:
       Master_public_key_path:
        Get_master_public_key: 0
            Network_Namespace:
1 row in set, 1 warning (0.01 sec)

## Built With

* [MySQL](https://www.mysql.com/) - Database server.

## Authors

* **Abhishek Kumar Yadav** - *Initial work* - [abhk943](https://github.com/abhk943)

## Acknowledgments

* [Toptal-Master-Slave](https://www.toptal.com/mysql/mysql-master-slave-replication-tutorial)