S3 versioning in AWS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is S3 versioning in AWS?

S3 versioning is a feature that keeps multiple versions of an object in the same bucket. It helps protect data from accidental deletion or overwriting by saving every change as a new version.

beginner

How do you enable versioning on an S3 bucket?

You enable versioning by going to the bucket settings in the AWS Management Console and turning on versioning. You can also enable it using AWS CLI or SDK by setting the bucket versioning status to 'Enabled'.

intermediate

What happens when you delete an object in a versioned S3 bucket?

When you delete an object in a versioned bucket, AWS adds a delete marker instead of removing the object permanently. Older versions remain and can be restored by removing the delete marker.

intermediate

Can you disable versioning on an S3 bucket after enabling it?

You cannot fully disable versioning once it is enabled. You can suspend versioning, which stops creating new versions but keeps existing versions intact.

beginner

Why is S3 versioning useful for data recovery?

Versioning allows you to recover previous versions of files if they are accidentally changed or deleted. This helps prevent data loss and supports audit trails for changes.

What does enabling versioning on an S3 bucket do?

A Keeps multiple versions of objects

B Deletes old objects automatically

C Encrypts objects by default

D Limits bucket size

Enabling versioning keeps multiple versions of objects to protect against accidental deletion or overwriting.

What is added to an object when you delete it in a versioned S3 bucket?

A A delete marker

B The object is permanently removed

C A backup copy

D A version lock

A delete marker is added instead of removing the object, allowing recovery of previous versions.

Can you completely turn off versioning after enabling it on an S3 bucket?

A Yes, anytime

B No, you can only suspend it

C Yes, but only after 30 days

D No, it stays enabled forever

You can suspend versioning to stop new versions but cannot fully disable it once enabled.

Which AWS tool can you use to enable versioning besides the console?

A AWS Lambda

B AWS CloudWatch

C AWS IAM

D AWS CLI

AWS CLI can be used to enable versioning by setting the bucket versioning status.

Why is versioning important for data protection?

A It encrypts data automatically

B It compresses data to save space

C It allows recovery of previous object versions

D It deletes old files to reduce clutter

Versioning allows you to recover previous versions if data is accidentally changed or deleted.

Explain how S3 versioning helps protect your data.

Think about what happens when you delete or overwrite files.

Describe the steps to enable versioning on an S3 bucket.

Consider both graphical and command line methods.

Practice

1. What is the main purpose of enabling S3 versioning on a bucket?

easy

A. To keep multiple copies of files automatically for recovery and tracking

B. To increase the storage capacity of the bucket

C. To encrypt files stored in the bucket

D. To restrict access to the bucket

Solution

1. Step 1: Understand what S3 versioning does

   S3 versioning keeps multiple versions of the same file automatically.

2. Step 2: Identify the main benefit

   This helps recover from mistakes and track changes over time.

3. Final Answer:

   To keep multiple copies of files automatically for recovery and tracking -> Option A

4. Quick Check:

   S3 versioning = multiple copies for recovery [OK]

Hint: Versioning means saving file copies automatically [OK]

Common Mistakes:

• Thinking versioning increases storage size limit
• Confusing versioning with encryption
• Assuming versioning controls access permissions

2. Which of the following is the correct way to enable versioning in an AWS S3 bucket configuration?

easy

A. versioning = true

B. versioning { enabled = true }

C. enable_versioning = yes

D. versioning: active

Solution

1. Step 1: Recall the syntax for enabling versioning

   Versioning is enabled by setting a block with enabled = true.

2. Step 2: Match the correct syntax

   Only versioning { enabled = true } matches the correct structure.

3. Final Answer:

   versioning { enabled = true } -> Option B

4. Quick Check:

   Enable versioning with block and enabled=true [OK]

Hint: Look for block with enabled = true syntax [OK]

Common Mistakes:

• Using assignment without block braces
• Using yes/no instead of true/false
• Using colon instead of equals sign

3. Given the following Terraform snippet for an S3 bucket, what will be the versioning state of the bucket after deployment?

resource "aws_s3_bucket" "example" {
  bucket = "my-versioned-bucket"

  versioning {
    enabled = false
  }
}

medium

A. Versioning will be enabled and keep all versions

B. Versioning will be enabled but only for new files

C. Versioning will be suspended, no new versions saved

D. Versioning will be enabled with MFA delete

Solution

1. Step 1: Check the versioning block value

   The snippet sets enabled = false, which means versioning is suspended.

2. Step 2: Understand suspended versioning behavior

   Suspended versioning means no new versions are saved, but existing versions remain.

3. Final Answer:

   Versioning will be suspended, no new versions saved -> Option C

4. Quick Check:

   enabled = false means versioning suspended [OK]

Hint: enabled = false means versioning suspended, not enabled [OK]

Common Mistakes:

• Assuming false means versioning enabled
• Confusing suspended with disabled (deleted)
• Thinking MFA delete is enabled by default

4. You wrote this Terraform code to enable versioning but it does not work as expected:

resource "aws_s3_bucket" "mybucket" {
  bucket = "mybucket"
  versioning = {
    enabled = true
  }
}

What is the error and how to fix it?

medium

A. enabled must be a string "true", not boolean true

B. Versioning cannot be enabled during bucket creation

C. Bucket name must be unique globally

D. versioning should be a block, not an assignment; remove '='

Solution

1. Step 1: Identify syntax error in versioning block

   The code uses versioning = { ... } which is incorrect syntax for a block.

2. Step 2: Correct syntax for versioning block

   Versioning must be declared as a block without '=' like versioning { enabled = true }.

3. Final Answer:

   versioning should be a block, not an assignment; remove '=' -> Option D

4. Quick Check:

   Blocks use braces without '=' [OK]

Hint: Blocks use braces without '=' sign [OK]

Common Mistakes:

• Using '=' with blocks
• Using string instead of boolean for enabled
• Ignoring bucket name uniqueness errors

5. You want to protect important files in your S3 bucket from accidental deletion but still allow updates. How does enabling versioning help achieve this, and what additional step should you take for stronger protection?

hard

A. Versioning keeps old file copies; enable MFA delete to require extra confirmation for deletions

B. Versioning encrypts files; enable bucket policies to restrict access

C. Versioning compresses files; enable lifecycle rules to archive old versions

D. Versioning increases storage; enable logging to track deletions

Solution

1. Step 1: Understand versioning's role in protection

   Versioning keeps all versions of files, so deleted files can be recovered.

2. Step 2: Identify additional protection for deletions

   Enabling MFA delete adds a requirement for multi-factor authentication to delete versions, preventing accidental or unauthorized deletions.

3. Final Answer:

   Versioning keeps old file copies; enable MFA delete to require extra confirmation for deletions -> Option A

4. Quick Check:

   Versioning + MFA delete = strong deletion protection [OK]

Hint: Use MFA delete with versioning for deletion safety [OK]

Common Mistakes:

• Confusing encryption with versioning
• Thinking lifecycle rules prevent deletions
• Assuming logging stops accidental deletes