EC2 Fundementals

Question 1

What is EC2?

Answer 1

EC2 = Elastic compute cloud, which is infrastructure as code

Question 2

What are the components of Elastic Compute Cloud (EC2)?

Answer 2

Elastic Compute Cloud is composed of :
• Renting virtual machines (EC2)
• Storing data on virtual drives (EBS)
• Distributing load across machines (ELB)
• Scaling the services using an auto-scaling group (ASG)

Question 3

What are the EC2 configuration Options?

Answer 3

• Operating System (OS):Linux, Windows or Mac OS
• How much compute power & cores (CPU)
• How much random-access memory (RAM)
• How much storage space:
• Network-attached (EBS & EFS)
• hardware (EC2 Instance Store)
• Network card: speed of the card, Public IP address
• Firewall rules: security group
• Bootstrap script (configure at first launch): EC2 User Data

Question 4

What are the different types of EC2 instances?

Answer 4

EC2 has different instances for different types of operations. these include,
general-purpose,
compute-optimized (batch process, HPCgaming),
memory-optimized (rds/non rds, caching), and
storage optimized(RDS and no SQL, OLTP, data warehousing)

Question 5

What are security groups?

Answer 5

These are a firewall around our EC2 instance that provides network security. These control how traffic goes into and out of our EC2 instance. They contain only allow rules.

Question 6

How many security groups can you attach to a single EC2 instance?

Answer 6

single 1 security grp or multiple security groups

Question 7

How many EC2 instances can a single security group be attached to?

Answer 7

can attach a security group to just 1 EC2 instance or multiple instances of EC2

Question 8

What are the default security group settings?

Answer 8

All inbound traffic is blocked by default

All outbound traffic is authorised by default

Question 9

Are security groups Multi AZ?

Answer 9

No, security groups are locked into a AZ.

Question 10

Can you attach a security group to multiple VPCs?

Answer 10

No, security groups are bound to VPC and sit outside of the EC2 instance.

Question 11

What is port 22 used for?

Answer 11

port 22 is for ssh into Linux Instance

Question 12

What’s the port number for FTP?

Answer 12

port 21

Question 13

What’s the SFTP port number?

Answer 13

port 22

Question 14

What traffic do ports 80 and 443 allow?

Answer 14

HTTP(80) and HTTPS(443)

Question 15

What’s the port number for the Windows instance

Answer 15

3389 = RDP (Remote Desktop Protocol)

Question 16

What are the different types of EC2 instances?

Answer 16

• On-Demand Instances: short workload, predictable
pricing
• Reserved: (MINIMUM 1 year)
• Reserved Instances: long workloads
• Convertible Reserved Instances: long workloads
with flexible instances
• Scheduled Reserved Instances: example – every
Thursday between 3 and 6 pm
• Spot Instances: short workloads, cheap, can lose
instances (less reliable)
• Dedicated Hosts: book an entire physical server,
control instance placement
• Dedicated Instances: no other customers will share
your hardware

Question 17

What’s the difference between spot instance and spot fleet?

Answer 17

A spot instance is a single instance and a spot fleet is set of spot instances or sometimes additional on-demand instances

Question 18

What is EC2 User Data?

Answer 18

EC2 User Data: Script launched at the first start of an instance

Question 19

How can a spot instance be terminated?

Answer 19

You need to first cancel the spot request and then terminate the instance. Cancelling a request doesn’t terminate the instance.