The promise of DBaaS like RDS is to reduce operational overhead (among other things) and one of the stellar cases is upgrades (major and minor). The suggested procedure involves just a couple of steps. For example, using AWS Console, you can enable “Auto minor upgrade” or modify the DB instance and schedule the upgrade to run in the next maintenance window.
But, both these options are risky because the upgrade process will start during the maintenance window but it is NOT guaranteed that the upgrade will be completed within the specified duration.
RDS performs a few extra steps to ensure the data consistency and rollback, making the minor version upgrade a time-consuming process:
- It takes a backup (if automated backups are enabled) prior to starting the upgrade process.
- Performs slow shutdown after setting …