EC2 - Fundamentals/Instance Types/Security Groups

Question 1

What does EC2 stand for?

Answer 1

Elastic Compute Cloud

Question 2

What is EC2 User Data?

Answer 2

A script that is bootstrapped only once when the EC2 instance is first launched. It is a script used to automate boot tasks such as:

Installing updates
Installing Software

Question 3

What are EC2 Instance Types?

Answer 3

They are types of instances that are optimised for different use cases.

Question 4

Dissect the following example instance type:

m5.2xlarge

Answer 4

m = instance class e.g. general purpose

5 = Generation (AWS improves this over time)

2xlarge = Size within the instance class

Question 5

What is the General Purpose instance type best used for and provide an example?

Answer 5

It’s great for diverse workloads such as web servers or code repositories.

It has a good balance of compute power, memory and networking.

Example: t2.micro

Question 6

What is the Compute Optimised instance type best used for?

Answer 6

Great for compute-intensive tasks that require high performance processors.

Use cases include:

Machine Learning
Dedicated gaming servers
High performance web servers

Question 7

What is the Memory Optimised instance type best used for?

Answer 7

Provides fast performance for workloads that process large data sets in memory.

Use cases include:

In memory databases

Question 8

What is the Storage Optimised instance type best used for?

Answer 8

Great for storage intensive tasks that require high, sequential read and write access to large data sets on local storage.

Use cases include:

Distributed file systems
Data warehousing applications

Question 9

What are security groups?

Answer 9

Security Groups act as a “firewall” on instances that control the inbound and outbound traffic for an EC2 Instance.

Question 10

True or False? Security Groups only contain allow rules

Answer 10

True

Question 11

List four things that security groups regulate for an EC2 Instance?

Answer 11

Access to ports
Authorised IP ranges (IPv4 and IPv6)
Control of inbound network
Control of outbound network

Question 12

True or False? Security groups can only be attached to a single EC2 Instance.

Answer 12

False. They can be attached to multiple instances. Also, instances can have multiple security groups attached to it

Question 13

True or False? Security groups are locked down to a region?

Answer 13

True

Question 14

How would you know if issues accessing the application is caused by the security group or not?

Answer 14

If there is a time out error, then it’s a security group issue.

If there’s a “connection refused” error, then it’s an application error or it’s not launched

Question 15

What is the default action for all inbound and outbound traffic?

Answer 15

All inbound traffic is blocked by default.

All outbound traffic is authorised by default.

Question 16

How would you allow other instances to be granted access to your main Instance?

Answer 16

By referencing the security groups attached to those instances in your security group e.g. authorise access from security group 1

Question 17

What are the two tools that use port 22? Explain what they are also

Answer 17

SSH (Secure Shell) - Log into a Linux instance

SFTP (Secure File Transfer Protocol) - Upload files using SSH

Question 18

What is FTP and what port does it use?

Answer 18

File Transfer Protocol allows you to upload files into a file share through port 21.

Question 19

What port allows you to access unsecured websites?

Answer 19

80 - HTTP

Question 20

What port allows you to access secured websites?

Answer 20

443 - HTTPS

Question 21

What is RDP and what port does it use?

Answer 21

Remote Desktop Protocol allows you to log into a Windows instance through port 3389.