Compute

Question 1

EC2 (Elastic Compute Cloud): 4 facts

Answer 1

1. Allows you to rent and manage virtual servers in the cloud.
2. AWS’s virtual servers are called instances.
3. Elastic - can grow or shrink based on the needs of, or the loads on your application
4. Uses virtual servers - compute or processing power in the cloud

Question 2

Amazon Machine Image (AMI) =

Answer 2

a preconfigured template to launch your instance

Question 3

4 Methods to manage an EC2 instance:

Answer 3

1. AWS Management Console - via web browser
2. SSH - from local computer
3. EC2 Instance Connect - no need to install an SSH client. EIC allows you to use IAM policies to control SSH access to your instances, removing the need to manage SSH keys.
4. AWS Systems Manager - allows you to manage your EC2 Instances via a web browser (interactive one-click browser based shell) or the AWS CLI

Question 4

The most common way to connect to a Linux EC2 Instance

Answer 4

via a Secure Shell (SSH)

Question 5

1. On-Demand Instances:

Answer 5

• fixed price billed down to the second, based on what you use. No contract.
  Common use cases:
• ideal for low cost without up-front payment or long-term commitment; unpredictable workloads that can’t be interrupted; for applications that are under development; for workloads that will not run longer than a year.

Question 6

2. Spot Instances

Answer 6

(least expensive option):
-Lets you take advantage of unused EC2 capacity. Your request is fulfilled only if capacity is available.
Common use cases:
- you are not concerned about the start or stop time of your application; your workloads can be interrupted; your application is only feasible at very low compute prices;
- you pay the spot price that’s in effect at the beginning of the hour; up to 90% less than on-demand.

Question 7

3. Reserved Instances

Answer 7

• RIs allow you to commit to a specific instance type in a particular region for 1 to 3 years.
  Common use cases:
• your application has/needs steady state usage; can commit to 1or 3 years; can pay upfront to receive a discount on on-demand prices; your application requires a capacity reservation.
• can save 75% off on-demand; requires a contract; can reserve capacity in an AZ for any duration; can pay all, partial, or no upfront - all upfront earns the highest discount.
• Provides convertible types at 54% discount - if you need additional flexibility (change the instance family, change the OS, etc.)

Question 8

4. Dedicated Hosts:

Answer 8

Allows you to pay for a physical server that is fully dedicated to running your instances.
Use cases:
- You want to bring your own server-bound software license from vendors like Microsoft or Oracle; you have regulatory or corporate compliance requirements around a tenancy model.
- can save up to 70% off on-demand prices; your bring your existing per-socket, per-core, or per-VM software licenses; the server is NOT shared with other customers (no multi-tenancy); a Dedicated Host is a physical server, whereas a Dedicated Instance runs on the host.

Question 9

5. Savings Plans:

Answer 9

Allows you to commit to compute usage (measured per hour) for 1 or 3 years.
Use cases:
- you want to lower your bill across multiple compute services; you want the flexibility to change compute services, instance types, OSs, or regions.
- you can save up to 72% off on-demand prices; you are not making a commitment to a Dedicated host, just compute usage; Saving can be shared across various compute services like EC2, Fargate, and Lambda; this does not provide a capacity reservation.

Question 10

Elastic Load Balancing:

Answer 10

automatically distributes your incoming application traffic across multiple EC2 instances. “The door greeter standing at the door, directing traffic”
Different types: (classic load balancers - deprecated); application load balancers; gateway load balancers; network load balancers.

Question 11

EC2 Auto Scaling

Answer 11

Uses horizontal scaling (or scaling out) - could go from 2 server instances to 3, or 3 down to 1 based on need. Auto (horizontal) scaling is very important because it reduces the impact of system failures and improves availability of your applications.

Question 12

Vertical scaling

Answer 12

“upgrading” (or scaling up), which upgrades and EC2 instance by adding more compute power (CPU, RAM) to an existing server.

Question 13

AWS Lambda is a:

Answer 13

serverless compute service that lets you run code without managing servers.

Question 14

You author code in Lambda by

Answer 14

functions, using many popular programming languages (The code you write is called a function)

Question 15

Lambda _____’s automatically

Answer 15

Scales

Question 16

Lambda allows developers to focus on core business logic for the apps they are developing, instead of:

Answer 16

managing servers - patching, provisioning, scaling, etc.

Question 17

With Lambda you ___ access servers

Answer 17

Cannot

Question 18

Lambda can execute your code in response to

Answer 18

events

Question 19

Lambda Functions have a ____ timeout

Answer 19

15 min

Question 20

With lambda, you are only responsible for the _____

Answer 20

Code. AWS manages the coding environment and the supported language versions

Question 21

With Lambda you are charged based on the ____ and ___

Answer 21

compute time duration and number of requests

Question 22

The Lambda free usage tier includes includes ______

Answer 22

1 million free requests each month

Question 23

An application in a container will run _____

Answer 23

the same every time, because it is a self-contained unit.

Question 24

AWS Fargate is a ___ compute engine for _____

Answer 24

Serverless, containers

Question 25

Fargate allows you to manage ____ similar to ____

Answer 25

Containers, Docker

Question 26

Fargate ____s automatically and is ___

Answer 26

scales, serverless

Question 27

Fargate works well with ___ and ___

Answer 27

Amazon Elastic Container Service (ECS) and Amazon Elastic Kubernetes (EKS)

Question 28

AWS Lightsail is a ___ that manages ___

Answer 28

Virtual Private Server, containers

Question 29

Lightsail allows you to quickly deploy ____ for small projects

Answer 29

pre-configured applications

Question 30

Lightsail includes (5 things):

Answer 30

Virtual machine, SSD-based storage, data transfer, DNS service management, and a static IP address

Question 31

AWS Outposts allows you to run AWS cloud services in your _____

Answer 31

Internal data center

Question 32

Outposts is an example of a ____ model

Answer 32

Hybrid

Question 33

Outposts support workloads that need to remain _____ due to _____ or ______

Answer 33

on-premises, latency, data sovereignty needs

Question 34

With Outposts, AWS actually ____ and ____ ___ in your ____

Answer 34

delivers and installs servers in your internal data center.
- used for a hybrid experience

Question 35

AWS Batch allows you to:

Answer 35

process large workloads in smaller chunks (or batches)

Question 36

AWS Batch is a

Answer 36

fully managed batch computing service that plans, schedules, and runs your containerized batch or ML workloads across a full range of AWS compute offerings.

Question 37

_______ is an event-driven, serverless computing platform that runs code in response to _____ and automatically manages the computing resources required by that code.

Answer 37

AWS Lambda, events