DBS-C01 Exam Dumps - AWS Certified Database - Specialty

Correct Answer: B

Explanation from Amazon documents:

Amazon ElastiCache for Redis is a fully managed in-memory data store that supports Redis, an open source, key-value database. Amazon ElastiCache for Redis provides several features to enhance the performance, availability, scalability, and security of your Redis data, such as cluster mode, global datastore, replication groups, snapshots, and encryption.

A global datastore is a feature that allows you to create a cross-Region read replica of your ElastiCache for Redis cluster. A global datastore consists of a primary cluster that is replicated across up to two other Regions as secondary clusters. A global datastore provides low-latency reads and high availability for your Redis data across Regions. A global datastore also supports encryption of cross-Region data transfers using AWS Key Management Service (AWS KMS).

To create a global datastore in ElastiCache for Redis, you need to do the following:

• Create a primary cluster in one Region. You can use an existing cluster or create a new one. The cluster must have cluster mode enabled and use Redis engine version 5.0.6 or later.
• Create a global datastore and add the primary cluster to it. You can use the AWS Management Console, the AWS CLI, or the ElastiCache API to create a global datastore.
• Create one or two secondary clusters in other Regions and add them to the global datastore. The secondary clusters must have the same specifications as the primary cluster, such as node type, number of shards, and number of replicas per shard.
• Enable encryption in transit and at rest for the primary and secondary clusters. Specify a customer master key (CMK) from AWS KMS for each cluster.

By creating a global datastore in ElastiCache for Redis and creating replica clusters in two other Regions, the database administrator can develop a caching solution that will be available across Regions and include low-latency replication and failover capabilities for DR. This solution will also meet the security requirement of encrypting cross-Region data transfers using AWS KMS. This solution will also require the least amount of operational effort, as it does not involve any data migration or manual intervention.

Therefore, option B is the correct solution to meet the requirements. Option A is not optimal because enabling cluster mode in ElastiCache for Redis and creating multiple clusters across Regions will not provide cross-Region replication or failover capabilities. Using AWS DMS to replicate the cache data by using AWS DMS will incur additional time and cost, and may not support encryption of cross-Region data transfers. Option C is not optimal because disabling cluster mode in ElastiCache for Redis and creating multiple replication groups across Regions will not provide cross-Region replication or failover capabilities. Using AWS DMS to replicate the cache data will incur additional time and cost, and may not support encryption of cross-Region data transfers. Option D is not optimal because creating a snapshot of ElastiCache for Redis in the primary Region and copying it to the failover Region will not provide low-latency replication or high availability for the Redis data across Regions. Using the snapshot to restore the cluster from the failover Region when DR is required will involve manual intervention and downtime.

https://docs .aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora-global-database-disaster-recovery.html

https://aws.amazon.c om/blogs/database/how-to-choose-the-best-disaster-recovery-option-for-your-amazon-aurora-mysql-cluster/

https://aws.amazon.com/about -aws/whats-new/2019/11/aurora-supports-in-place-conversion-to-global-database/

Correct Answer: A

Explanation from Amazon documents:

Performance Insights is a feature of Amazon Aurora MySQL that helps you quickly assess the load on your database and determine when and where to take action. Performance Insights displays a dashboard that shows the database load in terms of average active sessions (AAS), which is the average number of sessions that are actively running SQL statements at any given time. Performance Insights also shows the top SQL statements, waits, hosts, and users that are contributing to the database load.

Amazon DevOps Guru is a fully managed service that helps you improve the operational performance and availability of your applications by detecting operational issues and recommending specific actions for remediation. Amazon DevOps Guru applies machine learning to automatically analyze data such as application metrics, logs, events, and traces for behaviors that deviate from normal operating patterns. Amazon DevOps Guru supports Amazon RDS as a resource type and can monitor the performance and availability of your RDS databases.

By turning on Performance Insights for the Aurora MySQL database and configuring and turning on Amazon DevOps Guru for RDS, the database specialist can automatically detect and diagnose database performance issues and resolve bottlenecks faster. This solution will allow the database specialist to monitor the database load and identify the root causes of performance problems using Performance Insights, and receive actionable insights and recommendations from Amazon DevOps Guru to improve the operational performance and availability of the database.

Therefore, option A is the correct solution to meet the requirements. Option B is not sufficient because creating a CPU usage alarm will only notify the database specialist when the CPU utilization is high, but it will not help diagnose or resolve the database performance issues. Option C is not efficient because using the Amazon RDS query editor to get the process ID of the query that is causing the database to lock and running a command to end the process will require manual intervention and may cause data loss or inconsistency. Option D is not efficient because using the SELECT INTO OUTFILE S3 statement to query data from the database and saving the data directly to an Amazon S3 bucket will incur additional time and cost, and using Amazon Athena to analyze the files for long-running queries will not help prevent or resolve locking contention on the database.

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

With Amazon RDS, you can create a MariaDB, MySQL, Oracle, or PostgreSQL read replica in a different AWS Region from the source DB instance. Creating a cross-Region read replica isn't supported for SQL Server on Amazon RDS.

https://docs.aws.amazon.com/qldb/latest/developerguide/vpc-endpoints.html

"However, because you can encrypt a copy of an unencrypted DB snapshot, you can effectively add encryption to an unencrypted DB instance. That is, you can create a snapshot of your DB instance, and then create an encrypted copy of that snapshot. You can then restore a DB instance from the encrypted snapshot, and thus you have an encrypted copy of your original DB instance. For more information, see Copying a Snapshot." https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Overview.Encryption.html

The number of orders and exact schedule for the sale will vary each day. During the sale, approximately 10,000 concurrent users will look at the deals before buying items. Outside of the sale, the traffic volume is very low ==> Setting provisioning DynamoDB fix read 5000/write 10000 with will waste the resource when the traffic is low. It is not cost-effective.

You can restore a DB instance to a specific point in time (PITR), creating a new DB instance. To support PITR, your DB instances must have backup retention set to a nonzero value. https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/custom-backup-sqlserver.html

https://aws.amazon.com/blogs/database/setting-up-a-binlog-server-for-amazon-rds-mysql-and-mariadb-using-mariadb-maxscale/

"After you run the command, it’s okay to enable backup retention on the RDS instance by using the AWS CLI or the console. Enabling backup retention also enables binary logging."

https://aws.amazon.com/blogs/storage/point-in-time-recovery-and-continuous-backup-for-amazon-rds-with-aws-backup/