AWS Classroom Series – 01/Sept/2020

Simple Storage Service (S3)

• Amazon S3 lets you store & retrieve unlimited amounts of data from anywhere in the world at any time.
• S3 can be used to store any kind of file.
• S3 to store
  • Log files
  • Videos
  • Music
  • Images
• S3 can be used to host static websites (Websites with html & javascript & CSS)
• S3 stores blocks of raw data.
• Files in S3 are called as objects
• Objects are grouped together as buckets
• S3 bucket can hold objects(files) and folders
• Individual object(file) can be upto 5TB in size.
• S3 stores objects as key value pairs. Key is object name & value is your file.
• Lets try to create S3 bucket from AWS Console
• Navigate to s3 from AWS Services and click on create bucket
• Name of the bucket should be globally unique.
• Bucket is scoped to a region. AWS gives option to replicate buckets to other regions. This option is called as cross region replication.
• Lets create the following structure
  • three folders music, videos and images
  • upload one mp3 file in music which become an s3 object
  • similarly upload a video file into videos and an image in images folder
• S3 gives an https url to access the contents. (By default s3 will not allow public access)
• Lets try to access this location
• We need to understand how to give access to all or specific individuals.
• So to understand S3 better we need to know more details

S3 Storage Classes

• S3 is a service for storing files and the billing of s3 has two factors
  • size of the data
  • access costs
• Durability: Property which describes that the files are not lost or corrupted
• Availability: Property which determines the availability of files over https urls
• Understanding Durability:
  • Lets assume you have 100,000,000,000 objects with 99.999999999% durability
  • What does this mean?
    • This means you could expect to lose only 1 (0.000000001)% of objects over the year
  • Lets assume you have 100,000,000,000 objects with 99.99% durability, you might loose 10,000,000 objects in a year
• Understanding Availability:
  • Availability is percent of time an object will be available for accessing.
• The levels of availability and durability of an object depends on its storage class
• S3 Storage Classes:
  • STANDARD:
    • Durability: 99.999999999% (nine nines)
    • Availability: 99.99%
    • AZ’s: >2 (Data is copied into 2 AZ’s)
    • Cost of GB/month: 0.023$ (Us-west-2 region)
  • STANDARD_IA:
    • Designed for infrequent access. Here storage cost will be less and access cost will be more
    • Durability: 99.999999999%
    • Availability: 99.9%
    • AZ’s: >2 (Data is copied into 2 AZ’s)
    • Cost of GB/month: 0.0125$ (Us-west-2 region)
  • ONEZONE_IA:
    • Designed for infrequent & non critical data
    • Durability: 99.999999999%
    • Availability: 99.5%
    • AZ’s: 1 (Data is copied into 2 AZ’s)
    • Cost of GB/month: 0.01$ (Us-west-2 region)
  • Reduced Redundancy:
    • Durability: 99.99%
    • Availability: 99.99%
    • AZ’s: >2 (Data is copied into 2 AZ’s)
    • Cost of GB/month: 0.024$ (Us-west-2 region)
  • GLACIER:
    • For archival storage, you cannot access the data directly
    • Durability: 99.999999999%
    • Availability: varies
    • AZ’s: >2 (Data is copied into 2 AZ’s)
    • Cost of GB/month: 0.004$ (Us-west-2 region)
• Storage Classes for frequently accessed data
  • STANDARD
  • REDUCED_REDUNDANCY
• Storage Classes for infrequently accessed data
  • STANDARD_IA
  • ONEZONE_IA
• FOR Archival:
  • GLACIER
• IF YOU ARE NOT SURE
  • INTELLIGENT_TIERING
• Request and Data Retrieval costs

Access Permissions

• S3 offers the following methods to control access to objects
  • Bucket policies:
    • Resource-based policy that you apply to a bucket.
    • You can use bucket policies to grant access to all objects in a bucket or specific objects.
    • You can also control which users can read, write and delete objects
    • For this we need to create json based policies
  • User Policies:
    • Policies for Identity and Access Management (IAM) to S3 buckets
  • Bucket and object access control lists
    • This is legacy access control methods to give
      • anonymous read access to all
      • grant specific access to IAM Prinicipals

Note

• Refer PPT

AWS S3 bucket creation from cli

• Ensure AWS CLI is configured
• Refer Here for cli docs
• The s3 url format is s3://<bucketname>, so to create s3 bucket

aws s3 mb s3://<bucket-name>

• To view the buckets use

aws s3 ls

• To remove the bucket

aws s3 rb s3://<bucket-name>