PDF SAA-C03 Study Guide

This solution meets the requirement of reducing the number of database reads while ensuring high availability for a batch application that consists of a backend with multiple Amazon RDS databases. Amazon RDS read replicas are copies of the primary database instance that can serve read-only traffic. You can create one or more read replicas for a primary database instance and connect to them using a special endpoint. Read replicas can improve the performance and availability of your application by offloading read queries from the primary database instance.

Option B is incorrect because using Amazon ElastiCache for Redis can provide a fast, in-memory data store that can cache frequently accessed data, but it does not support replication from Amazon RDS databases. Option C is incorrect because using Amazon Route 53 DNS caching can improve the performance and availability of DNS queries, but it does not reduce the number of database reads. Option D is incorrect because using Amazon ElastiCache for Memcached can provide a fast, in-memory data store that can cache frequently accessed data, but it does not support replication from Amazon RDS databases.

References:

• https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html

https://aws.ama zon.com/blogs/security/rotate-amazon-rds-database-credentials-automatically-with-aws-secrets-manager/

By configuring scheduled scaling, the solutions architect can set the Auto Scaling group to automatically scale up to the desired compute level at a specific time (IAM) when the batch job starts and then automatically scale down after the job is complete. This will allow the desired EC2 capacity to be reached quickly and also help in reducing the cost.

This option is the most efficient because it uses AWS Storage Gateway, which is a service that connects an on-premises software appliance with cloud-based storage to provide seamless integration with data security features between your on-premises IT environment and the AWS storage infrastructure1. It also uses a stored volume gateway, which is a type of volume gateway that stores your primary data locally and asynchronously backs up point-in-time snapshots of your data to Amazon S32. It also runs the Storage Gateway software application on premises and maps the gateway storage volumes to on-premises storage, which enables you to use your existing storage hardware and network infrastructure. It also mounts the gateway storage volumes to provide local access to the data, which ensures that your data is available for low latency access on premises while also getting backed up to AWS. This solution meets the requirement of maintaining local access to all the data while it is backed up on AWS and ensuring that the data backed up on AWS is automatically and securely transferred. Option A is less efficient because it uses AWS Snowball, which is a physical device that lets you transfer large amounts of data into and out of AWS3. However, this does not provide a periodic backup solution, as it requires manual handling and shipping of the device. It also configures on-premises systems to mount the Snowball S3 endpoint to provide local access to the data, which could introduce additional complexity and latency. Option B is less efficient because it uses AWS Snowball Edge, which is a physical device that has onboard storage and compute capabilities for select AWS capabilities. However, this does not provide a periodic backup solution, as it requires manual handling and shipping of the device. It also uses the Snowball Edge file interface to provide on-premises systems with local access to the data, which could introduce additional complexity and latency. Option C is less efficient because it uses AWS Storage Gateway and configures a cached volume gateway, which is a type of volume gateway that stores your primary data in Amazon S3 and retains a copy of frequently accessed data subsets locally. However, this does not provide local access to all the data, as only some data subsets are cached locally. It also configures a percentage of data to cache locally, which could incur higher costs and complexity than using a stored volume gateway.