AWS Essentials

Question 1

What three things does an AWS account provide? Aside from those, what incidental protection does an account give an account holder?

Answer 1

A way to authenticate, authorize, and bill. An account automatically limits the blast radius for resources within a specific account.

Question 2

What is a principal?

Answer 2

An entity which can log into an AWS account.

Question 3

What does a principal need to do to interact with a system?

Answer 3

Authenticate.

Question 4

What mechanism does AWS use to authenticate and authorize principals?

Answer 4

IAM

Question 5

If a system has mitigated the effects of component failure and/or reduced the downtime required to recover after component failure, it can be said to be

Answer 5

Highly available

Question 6

If a system can continue to function despite the failure of a critical component, it can be said to be

Answer 6

Fault tolerant

Question 7

Which is easier to build and architect: a highly available system, or a fault tolerant system?

Answer 7

A highly available system is easier to build. Also less expensive.

Question 8

What is the process by which a completely failed system protects critical system data to build a new system in the event of failure?

Answer 8

Disaster recovery

Question 9

Do you need a DR plan if you’ve carefully crafted a HA or FT system?

Answer 9

Definitely.

Question 10

When evaluating a DR solution, the term that identifies the maximum allowable timeframe between system failure and the restoration of the system to an operational state.

Answer 10

RTO - Recovery Time Objective

Question 11

When evaluating a DR solution, the term that identifies the total amount of data you’ll lose based on time between failure and last successful backup.

Answer 11

RPO - Recovery Point Objective

Question 12

If data is local to a resource and is lost when the resource is released, it can be considered

Answer 12

Ephemeral

Question 13

If data exists in a secondary location as it’s passed between sources, it can be considered

Answer 13

Transient

Question 14

If data exists in a durable location which can survive system starts, stops, restarts, or power events, it can be considered

Answer 14

Persistent

Question 15

What’s an example of an ephemeral data store

Answer 15

Instance store volume, cache

Question 16

What’s an example of a transient data store

Answer 16

Queues (SQS, MQ), Kinesis Data Streams

Question 17

What’s an example of a persistent data store

Answer 17

EBS, EFS, S3

Question 18

What’s a common advantage of ephemeral storage

Answer 18

Speed!

Question 19

What’s a common disadvantage of persistent storage

Answer 19

Lack of speed, compared to ephemeral volumes.

Question 20

What’s the most common reason transient storage is used

Answer 20

Decoupling application components to help drive HA/FT designs

Question 21

What OSI layer represents the software stored on your device, and is capable of communicating in binary across a shared medium?

Answer 21

1 - Physical

Question 22

What OSI layer provides the ability to address devices uniquely, using a MAC address?

Answer 22

2 - Data link

Question 23

What OSI layer adds IP addresses?

Answer 23

3 - Network

Question 24

Is IP designed to be reliable?

Answer 24

Nope. Doesn’t test for receive, doesn’t account for ordering.

Question 25

What OSI layer adds TCP and UDP protocols?

Answer 25

4 - Transport

Question 26

What special capacity does the Transport layer enable?

Answer 26

Receipt confirmation and data ordering (via tcp/udp)

Question 27

What OSI layer adds ports?

Answer 27

5 - Session

Question 28

What special capacity do ports enable?

Answer 28

Multiple conversations (via multiple ports)

Question 29

What OSI layer generally adds encryption?

Answer 29

6 - Presentation

Question 30

What OSI layer generally implements standards of data exchange?

Answer 30

6 - Presentation

Question 31

What OSI layer generally implements data transmission protocols?

Answer 31

7 - Application (think HTTP, FTP, etc)