What all happens when we promote a read replica to separate RDS instance

Question

It took me more than 10 minutes to promote a read replica to a separate RDS instance. I saw the DB instance getting rebooted also in the case of EC2 RDS. Can someone please clearly explain to me the whole process?

Answer 1

The general process for promoting a read replica to a Single-AZ DB instance.

• Stop the transaction from writing to read replica source DB instance. Database updates occur on the read replica after they have occurred on the source DB instance.
•  Set the read_only parameter to 0 in the DB parameter group for the read replica to make changes to the read replica.
• Promote the read replica by using the Promote Read Replica option on the RDS console. 
• When the reboot is completed, The read replica will be available as a Single-AZ DB instance.

I hope this helps you.