Adding One More MySQL Slave to Cloud Based System (Amazon AWS)

MySQL Replication tends to be complex.

Creating a new slave to support your system expansion is not easier: coping large data files over the LAN, recovering replication, etc.

Fortunately, virtualization and SAN help us do it easier and faster.

Lucky us, Cloud Computing make it even easier.

Adding a New Slave is Easier than Ever

1. Select an existing slave that can be reboot w/o affecting the service.
1. Take the slave out of the production environment.
2. Stop the MySQL slave and perform a read lock: SLAVE STOP;FLUSH TABLES WITH READ LOCK;
3. Create an AMI based on this instance using AWS console or API.
4. Recover the instance upon AMI creation completion and get the slave back to production: UNLOCK TABLES;SLAVE START;SHOW SLAVE STATUS\G
2. Create a new slave based on the AMI
1. Launch a new slave using the AWS console or API.
2. Change the server's /etc/my.cnf file to fit a new slave instance:
1. Change the server-id=N value to a new numeric value.
2. Set relay-log='server-relay-bin' to the original slave server relay log name. (if you want to make it even easier, configure in the first slave's my.cnf relay-log=mysqld-relay-bin, and you'll be able to avoid this step).
3. Restart the MySQL instance: sudo /etc/init.d/mysql restart
4. Recover the MySQL: UNLOCK TABLES;SLAVE START;SHOW SLAVE STATUS\G
5. Add this new slave to the production environment.

Bottom Line

Expanding your business today is easier w/o the need for file copy or any other tedious action.

Keep Performing,

Moshe Kaplan