Better Availability of Databases with Amazon RDS

Answer - B.

The AWS Documentation mentions the following.

If you are looking to use replication to increase database availability while protecting your latest database updates against unplanned outages, consider running your DB instance as a Multi-AZ deployment.

For more information on AWS RDS, please visit the FAQ Link:

The correct answer is B. Multi-AZ.

Explanation: Amazon RDS (Relational Database Service) is a managed database service offered by AWS (Amazon Web Services) that makes it easier to set up, operate, and scale a relational database in the cloud. Multi-AZ is a feature of Amazon RDS that enables automatic failover to a standby replica in a different Availability Zone (AZ) in case of an outage in the primary AZ.

Here's a brief explanation of the other options given: A. VPC Peering: VPC (Virtual Private Cloud) peering is a networking connection between two VPCs that enables them to communicate with each other as if they are on the same network. While VPC peering is important for network connectivity, it does not directly contribute to the availability of databases.

C. Read Replicas: Read replicas are copies of a database instance that can be used to offload read traffic from the primary instance. They can also provide additional availability benefits as they can be used to promote to a primary database instance in case of a failure. However, read replicas do not provide automatic failover like Multi-AZ.

D. Data encryption: Data encryption is an important security feature, but it does not directly contribute to the availability of databases.

In summary, Multi-AZ is the feature of Amazon RDS that provides automatic failover to a standby replica in a different AZ, thereby ensuring better availability of databases.