Which solution should provide the HIGHEST level of reliability?
Migrate the database to an Amazon RDS MySQL Multi-AZ DB instance. Deploy the application in an Auto Scaling group on Amazon EC2 instances behind an Application Load Balancer. Store sessions in Amazon Neptune
Migrate the database to Amazon Aurora MySQL. Deploy the application in an Auto Scaling group on Amazon EC2 instances behind an Application Load Balancer. Store sessions in an Amazon ElastiCache for Redis replication group.
Migrate the database to Amazon DocumentDB (with MongoDB compatibility). Deploy the application in an Auto Scaling group on Amazon EC2 instances behind a Network Load Balancer Store sessions in Amazon Kinesis Data Firehose.
Migrate the database to an Amazon RDS MariaDB Multi-AZ DB instance. Deploy the application in an Auto Scaling group on Amazon EC2 instances behind an Application Load Balancer. Store sessions in Amazon ElastiCache for Memcached.
Explanations:
While using Amazon RDS MySQL Multi-AZ DB instances and EC2 Auto Scaling provides reliability, storing sessions in Amazon Neptune (a graph database) is not ideal for web application session management. A more appropriate solution would be a caching system like ElastiCache.
Migrating the database to Amazon Aurora MySQL offers higher availability and scalability than RDS MySQL. Deploying the application in an EC2 Auto Scaling group behind an Application Load Balancer ensures elasticity and availability. Using Amazon ElastiCache for Redis replication group offers a reliable, low-latency solution for session storage.
Amazon DocumentDB (with MongoDB compatibility) is not suitable for a MySQL-based application, which could cause compatibility issues. Additionally, Amazon Kinesis Data Firehose is not appropriate for session storage, as it is primarily used for streaming data to analytics services.
Although Amazon RDS MariaDB Multi-AZ DB instances and EC2 Auto Scaling offer reliability, MariaDB is not as scalable or feature-rich as Aurora MySQL. Storing sessions in ElastiCache for Memcached is less efficient than using Redis for session management, especially for highly available and persistent sessions.
If memory serves me right, the answer is:
Migrate the database to Amazon Aurora MySQL. Deploy the application in an Auto Scaling group on Amazon EC2 instances behind an Application Load Balancer. Store sessions in an Amazon ElastiCache for Redis replication group.