Elastic Compute Cloud
An application consists of a couple of EC2 Instances. One EC2 Instance hosts a web application and the other Instance hosts the database server. Which of the following changes can be made to ensure high availability of the database layer?
A. Enable Read Replicas for the database.
B. Enable Multi-AZ for the database.
C. Have another EC2 Instance in the same Availability Zone with replication configured.
D. Have another EC2 Instance in the another Availability Zone with replication configured.
D. Have another EC2 Instance in the another Availability Zone with replication configured.
Since this is a self-managed database and not an AWS RDS instance, options A and B are incorrect. To ensure high availability, have the EC2 Instance in another Availability Zone, so even if one goes down, the other one will still be available.
One can refer to the following media link for achieving high availability in AWS.
https://media.amazonwebservices.com/architecturecenter/AWS_ac_ra_ftha_04.pdf