It's not totally clear based on Amazon's provided documentation. Intuitively, it feels like it'd cost twice as much as a normal RDS instance for a two-zone deployment; does anyone here have experience with this, and could confirm or disconfirm that?
Amazon's RDS pricing page has two sections. One for Single-AZ Deployment and one for Multi-AZ Deployment.
Yes, Multi-AZ is about twice the price of Single-AZ. For example I see:
- db.t2.micro single - $0.017/hour
- db.t2.micro multi - $0.034/hour
To estimate the RDS cost I recommend the AWS Simple Monthly Calculator.
db.m4.large PostgreSQL instance I get the following:
- Single-AZ - $140.13/month - no High Availability
- Multi-AZ - $280.25/month
This means: Single-AZ cost = ½ Multi-AZ cost
Below two screenshots:
PS: no data transfer costs, no additional backup costs included