RDS Multi-AZ deployments Flashcards
What is Amazon RDS Multi-AZ deployment?
Amazon RDS Multi-AZ deployments provide enhanced availability and durability for Database (DB) instances, making them well-suited for production workloads. RDS automatically replicates the data to a standby instance in a different Availability Zone (AZ).
What is the difference between Multi-AZ deployments for RDS instances and RDS Aurora clusters?
For RDS instances, Multi-AZ deployments mean synchronous replication to a standby instance in a different AZ. For Aurora, it refers to multiple read replicas in different AZs, with one acting as the primary instance and the others as read replicas.
How does RDS Multi-AZ deployment impact database performance?
The primary impact is on write latency due to the synchronous replication to the standby instance. However, read performance can be improved by directing read traffic to read replicas if using Amazon Aurora.
Can you force a failover for an RDS Multi-AZ DB instance?
Yes, you can force a failover for RDS Multi-AZ DB instances manually by rebooting the primary DB instance with the AWS Management Console, AWS CLI, or RDS API and choosing the option to reboot with failover.
What happens during an RDS Multi-AZ failover?
During a failover, RDS automatically switches database operations to the standby replica. DNS records are updated to point to the standby DB instance, minimizing downtime. For Aurora, the system promotes a read replica to the primary role.
Why use RDS Multi-AZ deployment?
RDS Multi-AZ deployments are used to increase database availability, reduce the impact of maintenance events, and prepare for disaster recovery. It’s suitable for critical production environments.
How does Amazon Aurora provide fault tolerance across AZs?
Aurora automatically distributes copies of your data across multiple AZs, with each Aurora cluster containing up to 15 Amazon Aurora Replicas in addition to the primary instance; these replicas can be used for both read scaling and failover.
What are the cost implications of using RDS Multi-AZ?
Using RDS Multi-AZ deployments incurs higher costs due to the need to operate and maintain a standby replica of your database in a separate AZ. Aurora clusters also incur additional costs based on the number of replicas and the data transferred across AZs.
Does RDS Multi-AZ deployment offer read scaling?
RDS Multi-AZ deployments mainly provide high availability and failover capabilities. For read scaling, use RDS read replicas. However, Aurora clusters offer read scaling by allowing queries to be distributed across multiple Aurora Replicas.
How do you set up an RDS Multi-AZ deployment?
To set up RDS Multi-AZ, you can specify Multi-AZ deployment when you create a new DB instance. For existing DB instances, you can modify the instance and enable Multi-AZ deployment through the AWS Management Console, AWS CLI, or RDS API.
