AWS SAA-18: Amazon S3(Part-2)

S3 versioning, S3 replication, S3 storage class, Lifecycle rules, storage class analysis

S3 Versioning

• You can version your files in Amazon S3
• It is enabled at the bucket level
• Same key overwrite will change the version 1,2,3,….
• It is best practice to version your buckets
• — protect against unintended deletes (ability to restore a version)
• — easy roll back to previous version
• Note:
• — any file that is not versioned prior to enabling versioning will have version “null”
• — suspending versioning does not delete the previous versions

S3 Replication (CRR and SRR)

• Must enable versioning in source and destination buckets
• Cross-Region Replication and Same-Region Replication
• Buckets can be in different AWS accounts
• Copying is asynchronous
• Must give proper IAM permissions to S3
• Use case: CRR — compliance, low latency access, replication across accounts SRR — log aggregation, live replication between production and test account
• After you enable replication, only new objects are replicated
• Optionally, you can replicate existing objects using S3 Batch Replication
• — Replications existing objects and objects that failed replicating
• For DELETE operations:
• — can replicate delete markers from source to target
• — deletions with a version ID are not replicated (to avoid malicious deletes)
• There is no “chaining” of replication
• — if b1 has replication into b2, which has replication in b3, the objects created in b1 are not replicated to b3

S3 Storage Classes

— Durability

• High durability (99.99999999999%) of object across multiple AZ
• If you store 10,000,000 objects in S3, you can on average expect to incur a loss of a single object every 10,000 years
• Same for all storage classes

— Availability

• Measures how readily available a service is
• Varies depending on storage class
• E.g. S3 Std. has 99.99% availability = not available 53 minutes a year

1. S3 Standard — General Purpose

• 99.999% availability
• Used for frequently accessed data
• Low latency and high throughput
• Sustain 2 concurrent facility failures
• Use case: Big Data analytics, Mobile and Gaming application, content distribution

2. S3 — Infrequent Access

• For data that is less frequently accessed, but requires rapid access when needed
• Lower cost than S3 standard
• Amazon S3 Std-Infrequent Access (S3 Std-IA): 99.9% availability, use case — disaster recovery, backups
• Amazon S3 One Zone-Infrequent Access:
• — — high durability in a single AZ, data lost when AZ is destroyed
• — — 99.5% availability
• — — use case: storing secondary backup copies of on-premise data or data you can recreate

Amazon S3 Glacier Storage Classes

• Low-cost object storage meant for archiving backup
• Pricing: price for storage + object retrieval cost

3. Amazon S3 Glacier — Instant Retrieval

• Millisecond retrieval, great for data accessed once a quarter
• Minimum storage duration of 90 days

4. Amazon S3 Glacier — Flexible Retrieval

• Expedited(1 to 5 min), standard (3 to 5 hr), bulk (5 to 12 hr) — free
• Minimum storage duration of 90 days

5. Amazon S3 Glacier — Deep Archive

• For long term storage
• Standard (12 hr), bulk (48 hr)
• Minimum storage duration of 180 days

6. S3 Intelligent Tiering

• Small monthly monitoring and auto-tiering fee
• Moves objects automatically between Access Tiers based on usage
• There are no retrieval charges in S3 Intelligent Tiering

1. Frequent Access Tier(automatic): default Tier
2. Infrequent Access Tier(automatic): object not accessed for 30 days
3. Archive Instant Access Tier(automatic): object not accessed for 90 days
4. Archive Access Tier(optional): configurable for 90 days to 700+ days
5. Deep Archive Access Tier(optional): configurable from 180 days to 700+ days

Moving between Storage Classes

• You can transition objects between storage classes
• For infrequently accessed object, move them to standard IA
• For archive objects that you don’t need fast access to, move them to Glacier or Glacier Deep Archive
• Moving objects can be automated using a lifecycle rules

Lifecycle Rules

• Transition Actions: configure objects to transition to another storage class
• — Move object to standard IA class 60 days after creation
• — Move to Glacier for archiving after 6 months
• Expiration Action: configure objects to expire(delete) after some time
• — Access log files can be set to delete after 365 days
• — Can be used to delete old versions of files (if versioning is enabled)
• — Can be used to delete incomplete Multi-Part upload
• Rules can be created for a certain prefix
• Rules can be created for certain object tags

S3 Analytics — Storage Class Analysis

• Helps you decide when to transition objects to the right storage class
• Recommendations for standard and standard IA
• Does not work for One Zone-IA or Glacier
• Report is updated daily
• 24 to 48 hr to start seeing data analysis
• Good first step to put together Lifecycle Rules (or improve them)