Given the popularity and wide use of the open source MariaDB database in Amazon RDS, AWS has chosen to take things a step further. AWS has announced that it is extending the RDS SLA to cover MariaDB.
This means the following:
- The RDS SLA covers multiple Availability Zone instances for MariaDB.
- AWS commits to an uptime of 99.5% for these instances.
- AWS will provide a service credit in case it fails to deliver on these commitments.
Having multi-AZ instances is an important feature of this SLA. Each AZ is physically separate, highly-reliable and independent from each other.
Should the primary instance fail, the back up instance takes over, making sure that database functions go back to normal once failover is done.