AWS S3

S3 essentials

Static files. Set of name-key pairs. Buckets are grouping of information and have sub name spaces.

Busket names must be Unique across AWS.

S3 provides unlimited storage. 11 nines durability. 99.99% availability (Synced to multiple AZs)

Objects can be as small as 0 Bytes and as Large as 5TB.

Bucket limitations - 100 buckets per account at a time. Bucket ownership cannot be transferred once created. 

S3 security - All buckets/objects are private by default. ACLs for sharing S3 buckets with 2 different acounts. There are different bucket policies too(granting access to anonymous user, restricting access off of IP address, Restricting access based off HTTP referrer). Public content can be downloaded via URL. Signed URLs uses a key to create a unique URL; Can be done with API; time restrictions can be applied too.

S3 also has server side encryption.

S3 can be used to host static websites using route 53. S3 can act as an origin to the CloudFront CDN. Multi part upload facility available. Required for objects 5GB or larger. But suggested use is 100 MB and larger.

An uploaded object is synced across all AZs within that region.

Eventual consistency - If you upload an object and instantly make a read request, then your new object will be available.

S3 uses - Hosting static files, Origin for CloudFront CDN, Hosting static websites. Fileshare for networks, Backing up/Archiving (AWS Storage Gateway)

S3 Event Notification - events can be like RRSObjectLost (for recreation of lost RRS objects)

Events can be sent to SNS, LAmbda, SQS queue.