EC2 Fundamentals (Associate)

Question 1

What are some different capabilities of EC2 (Elastic Compute Cloud)

Answer 1

1. Renting virtual machines (EC2)
2. Storing data on virtual drives (EBS)
3. Distributing load across machines (ELB)
4. Scaling the services using an auto-scaling group (ASG)

Question 2

What are the different operating systems (OS) you can use for EC2 instances?

Answer 2

1. Linux
2. Windows
3. Max OS

Question 3

When configuring your EC2 what are things you have to consider?

Answer 3

1. Consider the what type of OS to use
2. How much compute lower & core (CPU)
3. How much random access memory (RAM)
4. How much storage space (network-attached such as EBS & EFS, also consider hardware such as EC2 instance store)
5. Network card: speed of the card, public IP address
6. Firewall rules
7. Bootstrap script (EC2 user data)

Question 4

It is possible to bootstrap your instances using _____________ scripts

Answer 4

EC2 user data scripts

Question 5

What does bootstrapping mean?

Answer 5

Launching commands when a machine starts

• So the script is only ran once at the instance first start and never ran again

Question 6

EC2 user data is used to automate boot task such as what?

Answer 6

• Installing updates
• Installing software
• Downloading common files from the internet
• Anything you can think of

Question 7

What is AWS naming conventions for its EC2 instances?

Answer 7

m5.2xlarge

m- is the instance class
5-is the generation (AWS improves them over time so when it upgrades it will be 6 n so on)
2xlarge- is the size within the instance class

Question 8

General purpose instances are great for what?

Answer 8

A diversity of workloads such as web servers or code repositories n they provide a good balance between compute, memory, networking (ex. t2.Mirco is a general purpose instance)

Question 9

Compute optimized instances are great for what?

Answer 9

-Batch processing workloads
-Media transcoding
-High Performance web servers
-High Performance Computing
-Scientific modeling & machine learning
-Dedicated gaming servers

They have a C and are great for compute - intensive task that require high performance processors

Question 10

What are memory optimized instances good for?

Answer 10

-High Performance relational/non-relational databases
- Distributed web scale cache stores
-In memory databases optimized for BI (business intelligence)
-Application performing real time processing of big unsaturated data

Are also great for fast performance for workloads that process large data sets in memory

Question 11

What are storage optimized instances good for?

Answer 11

They are great for storage intensive task that require high, sequential read and write access to large data sets on local storage

Can use them for:
- High frequency online transaction processing (OLTP) systems
-Relational & NoSQL databases
-Cache for in-memory databases
-Data warehousing applications
-Distributed file system

Question 12

___________ are the fundamental of network security in AWS where they control how traffic is allowed into or out of our EC2 instances and they only contain _______ rules and their rules can reference by IP or by __________

Answer 12

Security groups, allow rules, security group

Question 13

________ act as a firewall for your EC2 instances

Answer 13

Security groups

Question 14

What do security groups regulate?

Answer 14

They regulate:
- Access to Ports
- Authorized IP ranges (IPv4 & IPv6)
- Control of inbound network (from other to the instance)
- Control of outbound network (from the instance to other)

Question 15

Security groups can be attached to ________ instances

Answer 15

Multiple

Question 16

Security groups are locked down to a ____________

Answer 16

Region/VPC combination

Question 17

It’s good to maintain one separate security group for ________ access

Answer 17

SSH access

Question 18

If your application is not accessible (time out) then it’s a _______ issue and if it’s a connection refused error then it’s a ___________ issues or it’s not launched

Answer 18

Security groups issue, application error

Question 19

With security groups by default all inbound traffic is ______ and all outbound traffic is _________

Answer 19

Blocked, authorized

Question 20

What are the different ports?

Answer 20

• 22= SSH (secure shell)- log into a Linux instance
• 21 = FTP (file transfer protocol) - upload files into a file share
  -22= SFTP (secure file transfer protocol) - upload files using SSH

Question 21

Why are on demand instances good for?

Answer 21

Short workload, predictable pricing, pay by second

Question 22

What are the two different type of Reserved Instances (1 & 3 yr plan)

Answer 22

1. Reserved instances- good for long workloads
2. Convertible reserved instances- good for long workloads with flexible instances

Question 23

Savings Plans (1&3 yr commitment) EC2 Instances pricing option

Answer 23

God for committing to an amount of usage & long workloads

Question 24

Spot Instances

Answer 24

Good for short workload, cheap, and can loose instances (less reliable)

Question 25

Dedicated host

Answer 25

Book an entire physical server, control instance placement

Question 26

Dedicated instances

Answer 26

You decided when to start, launch, and kill the instance, no other customer will share your hardware

Question 27

Capacity reservations

Answer 27

Reserve capacity in a specific AZ for any duration

Question 28

With __________ you can reserve on demand instances capacity in a specific AZ for any duration and you have no time commitment and no billing discounts

Answer 28

capacity reservations

Question 29

With spot instances you have to define the _________ and get the instance while current spot price is less than _______ then you can keep the instance

Answer 29

Max spot price

Question 30

With spot instances what happens when the current spot price is greater than the max price?

Answer 30

You have 2 mins grace period to decided to stop or terminate your instance

Question 31

If you don’t want your spot instance you be claimed by AWS what other option can you do?

Answer 31

Use a spot block, which is a spot instance during a specified time frame ( 1 to 6 hours) without interruption

Question 32

What are the best use cases for spot instances?

Answer 32

For batch jobs, data analysis, or workloads that are resilient to failures and not great for critical jobs or databases

Question 33

When trying to terminate a spot instance what’s the first thing you must do?

Answer 33

Create a spot request

Question 34

What do you have to define when creating a spot request?

Answer 34

- Maximum Price - Desired number of instances - Launch specifications - Request type ( one time | persistent) - Valid from, Valid until

Question 35

With ________ spot request, as soon as your spot instances are fulfilled, your instances are going to be launched and then your spot instance will go away

Answer 35

One time

Question 36

With ________ spot request, then you want your number of instances to be valid as long as from the valid from to the valid until

Answer 36

Persistent

Question 37

If your spot request is persistent but for some reason you lost your spot instance (like it going over the max price) what will happen?

Answer 37

It will start an instance up and go into the spot request and when everything is validated it will restart everything for you

Question 38

If you want to cancel a spot instance, what state must it be in?

Answer 38

It must be in an open or active or disable state

Question 39

So when you want to cancel a spot request what is your responsibility?

Answer 39

You must terminate any instances you have launched from before

Question 40

When you want to terminate Spot instance for good what must you do?

Answer 40

Must cancel the spot request and then terminate your instances

Question 41

What is a spot fleet?

Answer 41

It’s a way for you to get a set of spot instances and it will try to meet the target capacity with price constraints

Question 42

What strategies is used to allocate spot instances in your spot fleet?

Answer 42

1. Lowest price- the spot fleet will launched instances from the pool that has the lowest price ( good for cost optimization) 2. Diversified- distribute instances across all pools (great for availability and long workloads) 3. Capacity optimized - pool with the optimal capacity for the number of instances 4. Price capacity optimized (recommended) - pool with highest capacity available, then select the pool with the lowest price (best choice for most workloads)

Question 43

Spot fleet will allow you to automatically request __________ with the lowest price

Answer 43

Spot instances