EC2

Question 1

What is an AMI?

Answer 1

Amazon Machine Image: Template for software configuration (operating system, application server, applications). Need to specify an AMI when you launch an instance.

Question 2

Billing

Answer 2

Pricing is per instance-hour consumed for each instance, from the time an instance is launched until it is terminated or stopped. Each partial instance-hour consumed will be billed per-second (minimum of 1 minute) for Linux or Ubuntu Instances and as a full hour for all other instance types.

Question 3

Dedicated Host

Answer 3

A physical server with EC2 instance capacity fully dedicated to your use. Useful for compliance needs.

Question 4

Dedicated Instance

Answer 4

EC2 instances that run in a VPC on hardware dedicated to a single customer. Physically isolated at the host hardware level. May share with other instances from same AWS account. Can still use RI purchasing for discounts.

Question 5

Elastic Block Storage (EBS) Volumes

Answer 5

Storage attached to EC2 instances

Question 6

Elastic Load Balancing

Answer 6

Feature of EC2, balances traffic across instances. Increases fault tolerance.

Question 7

Key Pairs

Answer 7

During the creation process of the Amazon EC2 instances you can create and download your key pair. This key pair is required when you want to connect to your Amazon EC2 instances.

Note: You can’t connect to your EC2 instance unless you attach a Security Group that allows SSH access from your IP.

Question 8

Payment Options/Plans

Answer 8

Payment Plans:
All Upfront = largest discount

Partial upfront = low upfront fee plus discounted rate

No Upfront = discounted hourly rate for term. One year at a time only.

Question 9

Pricing

Answer 9

Varies by storage capacity and instance type, AMI selected, region, data transfer in/out, and payment option selected.

On Demand: billed by second, minimum 1 minute.

Spot Instances: up to 90% discount, rates fluctuate based on Spot marketplace.

Reserved Instances: charged by hour regardless if usage occurs. Low up-front fee + discounted rate. 1 or 3 year terms.

• Convertible RI – discounted rate with ability to change configuration
• Standard RI – biggest discount but no changes
• Scheduled RI – launch in specified time range

Question 10

What is EC2?

Answer 10

EC2 provides scalable computing capacity in AWS cloud. Eliminates need to provision hardware up front, and allows you to launch as many or as few virtual servers as you need.

EC2 allows you to scale up or down to handle changes in requirements or spikes in popularity, reducing the need to forecast traffic.

Question 11

What are the components of launching an EC2 instance?

Answer 11

1. AMI (Amazon Machine Image): For software configuration
2. Instance type: For processing power, network speed, and memory
3. Storage: EBS, SSD, etc. Also storage amount
4. Configuration: IP addressing, VPC, subnet selection, IAM roles, and network interfacing
5. Security Groups
6. Tags: For labeling and cost segmentation
7. Key Pair: For access to the instance

Question 12

What are the three main categories of AMI’s?

Answer 12

1. Community AMI’s
   - Free to use
   - Generally, with these AMI’s you are just selecting the OS you want
2. AWS Marketplace AMI’s
   - Pay to use
   - Generally comes packaged with additional, licensed software
3. My AMI’s
   - AMI”s created on your AWS account

Question 13

What is the function of an instance type?

Answer 13

To specify the CPU power, network performance, and memory of an EC2 instance.

Question 14

What are the different families of instance types?

Answer 14

1. General purpose
2. Compute optimized
3. GPU optimized
4. Memory optimized
5. Storage optimized

Question 15

What are the EC2 purchasing options?

Answer 15

1. On Demand
2. Reserved
3. Spot
4. Savings Plans
5. Dedicated Host

Question 16

How does the on-demand purchasing option work?

Answer 16

Allows you to choose any instance type and provision or terminate it at any time.

1. Most expensive purchasing option
2. Most flexible purchasing option
3. Only charged when the instance is running and billed by the second

Question 17

How does the reserved purchasing option work?

Answer 17

Allows you to purchase an instance for a set time period of 1 or 3 years.

1. Allows for a significant price discount over on-demand
2. You can select to pay upfront, partial upfront, or no upfront
3. Once you buy a reserved instance, you own it for the selected time period and are responsible for the entire price, regardless of how often you use it.

Question 18

How does the Spot purchasing option work?

Answer 18

Allows you to bid on an instance type and then only pay for and use that instance type when the spot price is equal to or below your bid price.

1. This option allows Amazon to sell the use of unused instances, for short amounts of time, at a substantial discount
2. Spot prices fluctuate based on supply and demand in the spot marketplace
3. You are charge by the second, but bid pricing based on an hourly rate
4. When you have an active bid, an instance is provisioned for you when the spot price is equal to or less than your spot bid
5. Provisioned instances are automatically terminated when the spot price exceeds your spot bid

Question 19

What are the uses of an on-demand instance?

Answer 19

On-Demand instances are recommended for:

1. Users that prefer the low cost and flexibility of Amazon EC2 without any up-front payment or long-term commitment
2. Applications with short-term, spiky, or unpredictable workloads that cannot be interrupted
3. Applications being developed or tested on Amazon EC2 for the first time

Question 20

What are the uses of a reserved instance?

Answer 20

Reserved Instances are recommended for:

1. Applications with steady state usage
2. Applications that may require reserved capacity
3. Customers that can commit to using EC2 over a 1 or 3 year term to reduce their total computing costs

Question 21

What are the uses of a Spot instance?

Answer 21

Spot instances are recommended for:

1. Applications that have flexible start and end times
2. Applications that are only feasible at very low compute prices
3. Users with urgent computing needs for large amounts of additional capacity

Question 22

How does the savings plans purchasing option work?

Answer 22

Savings Plans offer significant savings over On Demand, just like EC2 Reserved Instances, in exchange for a commitment to use a specific amount of compute power (measured in $/hour) for a one or three year period.

Question 23

How does the dedicated host purchasing option work?

Answer 23

A Dedicated Host is a physical EC2 server dedicated for your use.

1. Can be purchased On-Demand (hourly).
2. Can be purchased as a Reservation for up to 70% off the On-Demand price.

Question 24

What are potential uses of a dedicated host?

Answer 24

Dedicated Hosts can help you reduce costs by allowing you to use your existing server-bound software licenses and can also help you meet compliance requirements.