RDS

Question 1

What are Read replicas used for? How many can I create?

Answer 1

For read scalability, we can have up to 15 read replicas

Question 2

What are the options for Read replicas?

Answer 2

AZ, cross AZ and cross regions

Question 3

Explain how read replicas are “populated”

Answer 3

They are updated async, and are eventually consistent

Question 4

Read replicas inside same AZ is free. True or false?

Answer 4

True

Question 5

What do we use RDS multi AZ for?

Answer 5

Typically disaster recovery

Question 6

How is multi AZ RDS different from Read replicas?

Answer 6

In RDS multi AZ there is one master db instance and the other ones are synchronously replicated.

Question 7

In Multi AZ RDS is the master instance always the same? If no, how do the application connects to DB?

Answer 7

No, any replicated instance can be promoted. Multi AZ gives us a DNS name that always point to the master DB

Question 8

Can Read replicas be set cross AZ for Disaster recovery?

Answer 8

Yes

Question 9

How to migrate RDS single AZ to Multi AZ?

Answer 9

Zero downtime, no need to shut down DB instance, juste click

Question 10

Difference between Aurora Read replicas and RDS replicas

Answer 10

Aurora read replicas can be promoted to master DB

Question 11

How to connect to aurora master instance and to a read replica?

Answer 11

Aurora provides a writer endpoint and a reader endpoint

Question 12

How Aurora disk storage handled?

Answer 12

There is shared storage that automatically scales from 10 to 128 GB

Question 13

Aurora reader endpoint is load balanced, true or false?

Answer 13

True