You are using a single Cloud SQL instance to serve your application from a specific zone.
You want to introduce high availability.
What should you do?
Click on the arrows to vote for the correct answer
A. B. C. D.D.
To introduce high availability for a Cloud SQL instance serving an application from a specific zone, the best option is to create a failover replica instance in the same region but in a different zone. Therefore, the correct answer is D.
Explanation:
Cloud SQL is a fully managed relational database service that supports MySQL, PostgreSQL, and SQL Server. High availability is one of the essential features of Cloud SQL that provides automatic failover to a standby instance in case of a primary instance failure.
A failover replica is a read replica that is configured to be promoted to the primary instance when the primary instance fails or becomes unavailable. Failover replicas provide automatic failover and high availability for Cloud SQL instances.
Creating a failover replica instance in the same region but in a different zone ensures that there is always a standby instance available to take over in case the primary instance fails. The failover replica is kept up to date with the primary instance through asynchronous replication.
Creating a read replica instance in the same region or a different region provides read scalability but does not provide high availability or automatic failover. Read replicas can improve the performance of read-intensive workloads by distributing read traffic across multiple instances.
Creating a read replica instance in a different region can also provide geographical redundancy and disaster recovery capability, but it does not provide high availability.
In summary, to introduce high availability for a Cloud SQL instance serving an application from a specific zone, we should create a failover replica instance in the same region but in a different zone.