Multi AZ
- An AWS feature that improves database availability and fault tolerance by automatically replicating data across multiple AZs
- If the primary database instance fails, AWS automatically fails over to a standby replica, minimizing downtime
- You need to ensure there is no single point of failure → prevent the chance of failure
- fail-over
- when you have to shift traffic to a redundant system in case the primary system fails
- common example is having a copy of your db where all ongoing changes are synced
- the copy is not in use until a failover occurs and it becomes the primary db