Technology Flashcards
What is Amazon EC2?
Elastic Cloud Compute.
This is the most popular part of AWS offering - run computing on EC2, store data on EBS, use ELB to distribute workload, scale with ASG. (
What can you choose / customise with an EC2 instance?
> OS: Linux/Windows > CPU > RAM > Storage (either EBS/EFS, or EC2 Instance Store) > Network card > Firewall & bootstrap
What are the different instance types available?
> general purpose: balance of compute, memory, and networking resources
compute optimized: ideal for compute-bound applications, such as gaming servers
memory optimized: fast performance, workloads process large datasets in memory
accelerated computing: use hardware accelerators (coprocessors) to perform some functions more efficiently
storage optimized: for high, sequential read and write access to large datasets on local storage
What are the different pricing options with EC2 instances?
> On demand > Saving Plans (1-year / 3-year) > Reserved Instances > Spot Instances > Dedicated hosts
What AWS service manages the adding / removing of instances in response to changing demand?
Amazon EC2 Auto Scaling
What methods can be used in EC2 Auto Scaling?
> Dynamic scaling: responds to changing demand.
> Predictive scaling: automatically schedules the right number of Amazon EC2 instances based on predicted demand.
What do you have to set with Amazon EC2 Auto Scaling?
> Min number of EC2 instances
Max number of EC2 instances
Desired number
What AWS Service directs incoming traffic between your EC2 instances?
Elastic Load Balancing (ELB)
What does ELB do?
Directs incoming traffic between your EC2 instances. It ensures:
> Decoupled architecture between your public facing resources, and private resources
> Workload is balanced between instances in use
What is Amazon Simple Notification Service (SNS)?
A pub/sub service - push notifications to users. E.g., send an email to an email list, or elicit an action of AWS Lambda functions.
What is Amazon Simple Queue Service (SQS)?
A message queuing service, to communicate between components/services in AWS.
What is Amazon Virtual Private Cloud?
It is a service to contain your resources in a logically isolated virtual network.
How do you allow access into your resources (VPC)?
Using an Internet Gateway
What service/product can you use to establish a private dedicated connection to your VPC?
AWS Direct Connect.
What do subnets do?
They group and separate different resources in the cloud.
What is a Network Access Control List (Network ACL)?
“Passport control” - subnet boundaries.
Define what traffic can enter and exit a subnet.
What is a Security Group?
“Doorman” - Instance boundaries
Defines what traffic can enter/exit an instance. By default, allows none in, and all out.
True / False: A Network ACL is Stateful.
False. A network ACL is Stateless. A Security Group is Stateful.
What is Amazon Route 53?
AWS’s Domain Name Service.
I.e., it translates website URLs into IP Addresses.
For an On Demand EC2 instance, what unit of time are you billed by?
> For a Linux instance, by the second (after the first minute)
For any other OS, by the hour
What type of Reserved Instances are there?
1) Convertible: You can change the instance type
2) Scheduled: Launch within the time window you reserve
Under the Shared Responsibility Model, who is responsible for operating-system patches and updates on EC2 Instances?
You (the customer).
The customer is responsible for operating-system patches and updates on EC2 Instances, as well as data security on the instances, Security Groups rules, etc.
What is an Instance Store?
Temporary memory attached to an EC2 instance. It is deleted between an Instance terminating and restarting.
What is an EBS Volume?
Elastic Block Store: A network drive you can attach to a specific instance for persistent storage.
What is a good (general) use case for EBS?
When you want to make block changes to a file / data object. E.g., change certain parts of a single 8GB video, using EBS, you can just change parts in isolation, rather than having to reupload all of the file.
What is an AMI?
Amazon Machine Image
They are a customization of an EC2 instance. You can use Public Amazon ones, or build your own.
What is EC2 Image Builder?
A service for automating VMs / other container images. E.g., create, maintain and validate EC2 AMIs, making changes as needed and pushing the AMI across instances across regions.
What is an EFS?
Elastic File System
It’s a managed “Network File System”, similar to an EBS but can be attached to 100s of EC2 Instances. (works only with Linux instances)
What are you responsible for in EC2 storage?
> Setting up backup / snapshots
Encryption
Data on drives
Understanding risk of Instance Stores
Which service can be used to automate image management processes?
EC2 Image Builder
What is Amazon S3?
Simple Storage Service: “Infinitely scaling storage”
What ways are there to control access to an S3 bucket?
Either (1) User based (using IAM), or (2) Resource Based, specifying rules for access to the Bucket.
What % availability is there for S3 Standard?
99.99%
What is AWS Storage Gateway?
AWS Storage Gateway is a hybrid cloud storage service that gives you on-premises access to virtually unlimited cloud storage.
How long is retrieval time in S3 Glacier Deep Archive?
You can retrieve data in 12 or 48 hours.
How long is standard retrieval time in S3 Glacier?
Standard retrieval usually takes between 3 and 5 hours to complete.
What does Amazon S3 Lifecycle Rules do?
Define when S3 objects should be transitioned to another storage class or when objects should be deleted after some time.
A research team deployed in a location with low-internet connection would like to move 5 TBs of data to the Cloud. Which service can it use?
AWS Snowcone: A small, portable, rugged, and secure edge computing and data transfer device. It provides up to 8 TB of usable storage.
What service will you use to set up a relational database on AWS?
Amazon Relational Database Service (RDS). Using this, you can set up a database using one of the following engines:
- Amazon Aurora
- PostgreSQL
- MySQL
- MariaDB
- Oracle Database
- Microsoft SQL Server
Why would you use RDS instead of deploying your own Database on EC2?
It’s a managed service, so it’ll take much less work.
What is one strength, and one drawback, or using Aurora over another RDS?
Strength: It’s supposed to be 3x / 5x faster than PostgreSQL and MySQL;
Weakness: It costs 20% more
What is AWS ElastiCache?
A fully managed in-memory data store, compatible with Redis or Memcached. Used to power applications with latency of sub-millisecond figures.
What is AWS DynamoDB?
A Serverless NoSQL Database. Very low latency, performance stays constant despite size.
What is Amazon Redshift?
A managed Data Warehouse service on AWS - used primarily for analysis of historical data, rather than the instant read/write functions to RDS/Aurora.
What is Amazon EMR?
Elastic MapReduce - helps creating Hadoop cluster to cluster hundreds of EC2 instances to work together to analyse data.
What is AWS Athena?
A serverless database with SQL capabilities, where you pay per query.
It’s used to query data in S3, for one-time-use queries.
What is Amazon Quicksight?
Serverless BI tool to create dashboards.
What is Amazon DocumentDB?
Amazon’s version of MongoDB (no-SQL database). It’s similar to DynamoDB, although you do more things manually, such as select the number of instances for the cluster and the instance sizes.
What is Amazon Neptune?
A fully managed graph database.
What is Amazon QLDB?
Quantum Ledger Database. Used to review all changes to your data over time. E.g. good for a ledger database.
What is Amazon DMS?
Database Migration Service.
Supports homogenous migrations (e.g. just straight lift over), or heterogeneous (move to a new database engine, manage the required changes).
What is AWS Glue?
A managed ETL service.
What is Amazon Managed Blockchain?
It’s a managed decentralised blockchain service.
What is Amazon ECS?
Elastic Container Service. It’s used to launch Docker containers on AWS.
What is Amazon EKS?
Elastic Kubernetes Service. Used for Kubernetes clusters.
What is Amazon Fargate?
Serverless option for ECS.
What is Amazon Lightsail?
Lightsail is an easy-to-use cloud platform that offers everything needed to build an application or website (light touch do everything with little personal configuration).
What is the Elastic Container Registry (ECR)?
A service where you store your Docker image so they can be run by ECS or Fargate.
What is Amazon CloudFormation?
Basically, a tool to easily manage all the infrastructure around your resources (Instances, Storage, Auto-Scaling, ELBs, etc), via templates.
What is Amazon Elastic Beanstalk?
A PaaS to help developers, by setting all the infrastructure automatically!
What is AWS CodeDeploy?
A service to help manage the deployment of new code across all your instances at once (and local servers too, if present).
What is AWS CodeCommit?
A source-control repository hosted on AWS (e.g. the same as Github, Bitbucket, etc.)
What is AWS Cloud9?
An in the cloud IDE.
With HTTP and HTTPS traffic, what feature of an Application Load Balancer can be used to bind a user’s session to a specific instance?
Sticky sessions
With EC2 instances, which of the following is a snapshot of a particular state of that resource?
Golden image
What are Amazon S3 Lifecycle Rules?
Amazon S3 Lifecycle Rules can be used to define when S3 objects should be transitioned to another storage class or when objects should be deleted after some time.
