mysql replication

1. MySQL Replication

2. Agenda
• • Basics of Replication
• • Why Replication Needed
• • Types Of Replication
• • Replication For MySQL
• • Configuring MySQL Replication
• • Testing a Replicated MySQL System

3. Basics of Replication
• • Master / Slave, Master / Master, and Circular
replication
• • Master writes all DDL and DML statements
in binary log
• • Slaves read the binary log and run queries
locally
• • A master can have many slaves; a slave only
one master
• • MySQL Replication is asynchronous

4. Master - Slave and Master-Master
Replication Architecture
• • Master – Slave: Master handles writes, slave
handles reads
• • Master – Master: Both act as master and
slave for each other

5. Circular Replication Architecture
• • Multiple masters connected in a circular
chain
• • Each master acts as a slave to the next
master

6. Why Replication Needed
• • Using Replication for Backups
• • Different storage engines for performance
• • Scale-Out (Splitting load between servers)
• • Reporting system on slave

7. Types Of Replication
• • Synchronous Replication
• • Asynchronous Replication

8. Synchronous Replication
• • Master waits for data to be recorded on
replicas
• • Two-phase commit ensures data integrity
• • Not implemented in MySQL

9. Asynchronous Replication
• • Write considered complete when local
storage acknowledges
• • Performance increases, but risk of
inconsistency
• • Slaves need not be connected permanently

10. Considerations Before Setting
Replication
• • MySQL versions of servers should match
• • Ensure communication between master and
slave

11. How to Set MySQL Replication
• 1. Configure replication user on master
• 2. Enable binary log and set server-id
• 3. Restart master
• 4. Take backup from master
• 5. Configure slave and restore backup
• 6. Use CHANGE MASTER and START SLAVE

12. Configure my.cnf
• Master configuration:
• server-id=1
• log-bin=mysql-bin
• Slave configuration:
• server-id=2
• relay-log=relay-bin

13. Configure Slave Server
• Use the CHANGE MASTER TO command:
• CHANGE MASTER TO
• MASTER_HOST='192.168.9.236',
• MASTER_USER='repl',
• MASTER_PASSWORD='repl@123',
• MASTER_LOG_FILE='mysql-bin.000004',
• MASTER_LOG_POS=108;

14. Known Issues and Resolutions
• • Replication can fail silently; monitor
regularly
• • Use checksum tools (Percona) to verify
tables
• • Compare tables and resync if needed
• • Monitor logs and replication lag

15. Thank You
• Prepared by: VITS Anil
• Questions?
• Feel free to reach out for clarifications.