Aws Overview

Front 1

What are the 3 computing models that AWS makes use of?

Back 1

• Infrastructure as a service (IaaS)

• Platform as a service (PaaS)
• Software as a service (Saas)
  

Front 2

What's the difference between IaaS and PaaS?

Back 2

IaaS is more flexible but higher admin overhead, where you can manage your lifecycle. Paas is less flexible but abstracts a lot more (like Cpanel gives you less choice but less to go wrong)

Front 3

What are 2 characteristics of Saas?

Back 3

• Upgrades are centralised with vendor
  
• Payment/Subscription model

Front 4

What is cloud vs hybrid solution?

Back 4

A cloud solution runs entirely in the cloudwhereas a hybrid might call out to the cloud, or into a corporation DMZ

Front 5

What is on premise when using AWS?

Back 5

When you still use AWS components and techniques but runs on a company's servers rather than Amazon's.

Front 6

What is an AWS Region? There are two parts to the definition.

Back 6

A physical location containing multiple Availability Zones

Front 7

What is an Availability Zone? There are two parts to the definition.

Back 7

A group of data centres in a region that collaborate/have redundancy

Front 8

What is the segregation of Regions and Availability zones? There are 2 points.

Back 8

• Regions are isolated from each other altogether
• Availability zones within a region are isolated but communicate through low latency links
  

Front 9

What is the shared responsibility model?

Back 9

AWS keeps the cloud itself secure, you choose the security setup to secure your apps as if you were running on site.

Front 10

How do we script up AWS services?

Back 10

Via the AWS CLI

Front 11

How do the same in Java?

Back 11

Using the SDK

Front 12

What is EC2? There are 2 parts to the definition

Back 12

The web service that provides resizable compute capacity

Front 13

What is ECS and how does it relate to ECR?

Back 13

A container management service for Docker containers - it uses ECR as a registry, similar to Dockerhub.

Front 14

What is Lightsail?

Back 14

An preconfigured, cookie cutter setup for a Virtual Private Server

Front 15

What is AWS Batch? There are 2 parts.

Back 15

• A setup to run large numbers of jobs
• Can choose based on whether you need CPU or memory as a priority
  

Front 16

What is AWS Elastic Beanstalk? Name 2 things it does.

Back 16

The tooling to scale your apps up and out, and cut them over

Front 17

What is Lambda?

Back 17

A way of running just code, no server required!

Front 18

What is S3? There are two parts

Back 18

Object storage, with a web interface to create/update

Front 19

What is EBS?

Back 19

Elastic Block Store - Basically disk space

Front 20

How does this differ from S3?

Back 20

S3 is an abstraction of storage, rather than something closer to file writing in Java

Front 21

What is the Amazon Elastic File System?

Back 21

A file system plan where you pay as you go for usage

Front 22

What are the DB options provided by AWS?

Back 22

• Aurora
• Amazon RDS
• Amazon Dynamo DB
• Amazon ElastiCache

Front 23

What is Aurora ?

Back 23

Relational DB engine for use with MySQL and PostGres

Front 24

What is RDS?

Back 24

A service for setting up and administering relational Databases

Front 25

What is Dynamo?

Back 25

A no-SQL database service

Front 26

What is ElastiCache?

Back 26

A web-service to setup an in memory cache in the cloud

Front 27

What are two engines that support ElastiCache?

Back 27

Redis and Memcached

Front 28

What is Amazon VPC?

Back 28

Virtual Private Cloud - a way of setting up your 'part' of the cloud with subnets and routing tables etc, as if it was your own network

Front 29

What is Amazon Cloudfront?

Back 29

A CDN service

Front 30

What is Route 53?

Back 30

Amazon's DNS web service

Front 31

What is ELB?

Back 31

Load balancing technology to ensure that underlying EC2 instances get hit evenly

Front 32

What is IAM?

Back 32

The tool to manage users, groups and permissions (Identity Access Management)

Front 33

What is Kinesis?

Back 33

A platform for Streaming

Front 34

What is SQS?

Back 34

Equivalent to a JMS Queue

Front 35

What is a SNS?

Back 35

Like a JMS topic

Front 36

How do regions and availability zones keep data up to date if they're segregated?

Back 36

Data/Config can be replicated across both physical (Geographic) region or different Availability Zones within different AWS regions

Front 37

Regions are isolated from eachother to provide the greatest fault tolerance -why would this work?

Back 37

• Redundancy is only one part of fault tolerance, segregation is another facet - if one region has a problem, other regions aren't affected because of this segregation.
• One disaster doesn't bring the whole house down

Front 38

What is the difference between putting your data in multiple regions as opposed to multiple availability zones within a single region?

Back 38

• You can't see 'across regions' by design (for example, to see data in ap-southeast-2 that originated in is-east-1, this data must be copied).
• By contrast, putting data across availability zones in a region is for fault tolerance.
• Can think of the former being a conscious design decision, whereas the latter is an everyday practice

Front 39

Is the availability zone transparent to the user? How about the region?

Back 39

• It's not transparent in as much as availability zones are specified by you, but you still don't control the precise data centre by specifying a zone - this is done by AWS to distribute usage across data centres.
• The region on the other hand is a lot more explicit, if you say ap-southeast-2, you really are choosing it!

Front 40

What are step functions used for?

Back 40

An alternative to SQS or MQ - a way of moving data between apps in a serverless fashion

Front 41

What is Amazon SWF (Simple Workflow) used for?

Back 41

A runner for background jobs that need orchestration of some kind

Front 42

What is EC2 auto-scaling?

Back 42

A way of spinning instances up and down based on criteria without human involvement

Front 43

What is fargate? There are 2 parts.

Back 43

• Running containers without having manage servers or clusters
• Specify your memory and CPU, not the actual instance you want to run it on.

Front 44

What is serverless repo?

Back 44

A place to run lambdas

Front 45

What is cloudwatch? There are 3 parts

Back 45

• Something to gather metrics
• Something to log applications
• Something to display events

Front 46

What technologies can auto-scaling apply to?

Back 46

• RDS
• EC2
• Dynamo
• ECS tasks

Front 47

What is cloudformation?

Back 47

Grouping related AWS resources into units and having a template to make them a reality

Front 48

What is the API Gateway?

Back 48

The 'front door' to your applications from the outside world (when said apps are API endpoints)

Front 49

What are the 3 types of load balancing and their strategies?

Back 49

• Classic - for EC2 use only
• Application - HTTP/S level - at connection level
• Network - TCP level - used for extreme performance