RDS Aurora Elasticache

Question 1

RDS, an AWS managed service, uses SQL as the query language. True or False?

Answer 1

True

Question 2

Which one of the following databases are not supported by AWS RDS? (Pick 2)

a) Cassandra

b) Oracle

c) Postgress

d) MySQL Server

e) MongoDB

Answer 2

A & E

RDS allows MariaDB, Postgress, MySQL, Oracle, Microsoft SQL Server, and Aurora

Question 3

Which of the following features is not available for the AWS RDS service

a) Storage backed by EBS (gp2 or io1)

b) Multi AZ set up for DR

c) Read replicas for improved scalability

d) SSH into RDS instances

e) Point In Time restore

f) Automated Provisioning, OS patching

Answer 3

d)
Because AWS RDS is a managed instance, we do not have access to the underlying EC2 instance

Question 4

AWS RDS does not support autoscaling in which RDS detects the DB is running out of space and scales automatically. True or False

Answer 4

False

RDS detects you are running out of space and scales automatically there by avoiding a manual intervention. You have to set the Maximum Storage Threshold.

Storage gets modified under these conditions:

• Free Storage is < 10% of allocated storage
• Low-Storage lasts at least 5 minutes
• 6 hours have passed since last modification

Useful for applications with unpredictable workload

Question 5

Which AWS RDS feature helps with scaling reads? Read Replicas or Multi AZ set up ?

Answer 5

Read Replicas

RDS can have upto 15 read replicas
Within AZ, Cross AZ, or Cross Region

Question 6

The RDS Read Replication is synchronous in nature so its in highly consistent. True or False?

Answer 6

False
RDS Read replication is asynchronous so reads are eventually consistent.

The read replicas can become its own database and take writes

Question 7

Which RDS feature enables a micro service to implement the CQRS design pattern?

Answer 7

Asynchronous Read Replica. The application will only allowed to read from the read replica without affecting the write instance.

Question 8

In AWS there is a network cost when data goes from one AZ to another. The same rule applies to AWS RDS when replicas are within the same AZ or same region. True or False?

Answer 8

False
While its true there is network cost associated when data goes from one AZ to another, under AWS RDS, which is a managed service, if AZs are within the same region, there is no cost. There is a cost if data goes from one region to another

Question 9

AWS RDS Multi AZ is mainly used for Disaster Recovery. True or False?

Answer 9

True
Since there is one DNS name the fail over happens automatically. The failure can be due to AZ, network, or storage. No changes needed in the application

Question 10

AWS RDS Multi AZ has an RDS standby instance that is replicated synchronously. True or False?

Answer 10

True
The read replicas can also be setup as multi AZ for DR

Question 11

In a AWS Aurora cluster, what are the endpoints that can be used to implement CQRS?

Answer 11

Writer Endpoint (connected to master) and Reader Endpoint (connection load balancing)

Question 12

What does Redis stand for?

Answer 12

Remote Dictionary Service

Question 13

Default port for FTP

Answer 13

21

Question 14

Default port for SSH

Answer 14

22

Question 15

Default port for SFTP

Answer 15

22 (same as SSH)

Question 16

Default port for HTTP

Answer 16

80

Question 17

Default port for HTTPS

Answer 17

443

Question 18

Default port for Postgress

Answer 18

5432

Question 19

Default port for MySQL

Answer 19

3306

Question 20

Default port for Oracle

Answer 20

1521

Question 21

Default port for MS SQL

Answer 21

1433

Question 22

Default port for MariaDB

Answer 22

3306 (same as MySQL)

Question 23

Default port for Aurora

Answer 23

5432 (Postgress) 3306 (My SQL)