Section 6: RDS + Aurora + ElastiCache Flashcards
My company would like to have a MySQL database internally that is going to be available even in case of a disaster in the AWS Cloud. I should setup
A) Read Replicas
B) Encryption
C) Multi AZ
C) Multi AZ
In this question, we consider a disaster to be an entire Availability Zone going down. In which case Multi-AZ will help. If we want to plan against an entire region going down, backups and replication across regions would help.
Our RDS database struggles to keep up with the demand of the users from our website. Our million users mostly read news, and we don’t post news very often. Which solution is NOT adapted to this problem?
A) An ElasticCache Cluster
B) RDS Read Replicas
C) RDS Multi AZ
C) RDS Multi AZ
Be very careful with the way you read questions at the exam. Here, the question is asking which solution is NOT adapted to this problem. ElastiCache and RDS Read Replicas do indeed help with scaling reads.
We have setup read replicas on our RDS database, but our users are complaining that upon updating their social media posts, they do not see the update right away
A) There must be a bug in our application
B) Read Replicas have asynchronous replication and therefore it’s likely our users will only observe eventual consistency
C) We should have setup multi-az instead
B) Read Replicas have asynchronous replication and therefore it’s likely our users will only observe eventual consistency
Which RDS Classic (not Aurora) feature does not require us to change our SQL connection string?
A) Read Replicas
B) Multi AZ
B) Multi AZ
Multi AZ keeps the same connection string regardless of which database is up. Read Replicas imply we need to reference them individually in our application as each read replica will have its own DNS name
You want to ensure your Redis cluster will always be available
A) Enable Read Replicas
B) Enable Multi AZ
B) Enable Multi AZ
Multi AZ ensures high availability
Your application functions on an ASG behind an ALB. Users have to constantly log back in and you’d rather not enable stickiness on your ALB as you fear it will overload some servers. What should you do?
A) Create your own Load Balancer and deploy that on EC2 instances
B) Store session data in RDS
C) Store session data in ElasticCache
D) Store session data in shared EBS Volume
C) Store session data in ElasticCache
Storing Session Data in ElastiCache is a common pattern to ensuring different instances can retrieve your user’s state if needed.
One analytics application is currently performing its queries against your main production database. These queries slow down the database which impacts the main user experience. What should you do to improve the situation? A) Setup a Read Replica B) Setup Multi AZ C) Run the analytics queries at night D) Increase the RDS Instance Size
A) Setup a Read Replica
Read Replicas will help as our analytics application can now perform queries against it, and these queries won’t impact the main production database.
You have a requirement to use TDE (Transparent Data Encryption) on top of KMS. Which database technology does NOT support TDE on RDS?
A) PostgreSQL
B) Oracle
C) MS SQL Server
A) PostgreSQL
Which RDS database technology does NOT support IAM authentication?
A) Oracle
B) PostgresSQL
C) MySQL
A) Oracle
You would like to ensure you have a database available in another region if a disaster happens to your main region. Which database do you recommend? A) RDS Read Replicas B) RDS Multi AZ C) Aurora Read Replicas D) Aurora Global Database
D) Aurora Global Database
Global Databases allow you to have cross region replication
How can you enhance the security of your Redis cache to force users to enter a password?
A) Use Redis Auth
B) Use IAM Auth
C) Use Security Groups
A) Use Redis Auth
Your company has a production Node.js application that is using RDS MySQL 5.6 as its data backend. A new application programmed in Java will perform some heavy analytics workload to create a dashboard, on a regular hourly basis. You want to the final solution to minimize costs and have minimal disruption on the production application, what should you do?
A) Enable Multi-AZ for the RDS database and run the analytics workload on the standby database
B) Create a Read Replica in a different AZ and run the analytics workload on the replica database
C) Create a Read Replica in a different AZ and run the analytics workload on the source database
D) Create a Read Replica in the same AZ and run the analytics workload on the replica database
D) Create a Read Replica in the same AZ and run the analytics workload on the replica database
this will minimize cost because the data won’t have to move across AZ
You would like to create a disaster recovery strategy for your RDS PostgreSQL database so that in case of a regional outage, a database can be quickly made available for Read and Write workload in another region. The DR database must be highly available. What do you recommend?
A) Create a Read Replica in the same region and enable multi-AZ on the main database
B) Create a Read Replica in a different region and enable multi-AZ on the main database
C) Create a Read Replica in the same region and enable multi-AZ on the read replica
D) Enable Multi-Region on the main database
B) Create a Read Replica in a different region and enable multi-AZ on the main database
You are managing a PostgreSQL database and for security reasons, you would like to ensure users are authenticated using short-lived credentials. What do you suggest doing?
A) Install PostgreSQL on EC2 and install the pg_iam module. Authenticate using IAM username and password
B) Use PostgreSQL for RDS and install the pg_iam module. Authenticat using IAM username and password
C) Use PostgreSQL for RDS and authenticate using a token obtained through the RDS service
D) Use PostgreSQL for RDS and force SSL connections. Authenticate using SSL certificates that you regularly rotate
C) Use PostgreSQL for RDS and authenticate using a token obtained through the RDS service
In this case, IAM is leveraged to obtain the RDS service token, so this is the IAM authentication use case.
An application is running in production, using an Aurora database as its backend. Your development team would like to run a version of the application in a scaled-down application, but still, be able to perform some heavy workload on a need-basis. Most of the time, the application will be unused. Your CIO has tasked you with helping the team while minimizing costs. What do you suggest?
A) Use an Aurora Global Database
B) Use an RDS database instead
C) Use Aurora Serverless
D) Run Aurora on EC2, and write a script to shut down the EC2 instance at night1
C) Use Aurora Serverless
