S3 versioning in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

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

You have enabled versioning on an S3 bucket. You delete an object named photo.jpg. What is the state of the object after deletion?

A A delete marker is added, hiding the latest version but previous versions remain accessible.

B The object is archived to Glacier automatically.

C The object is copied to a backup bucket before deletion.

D The object is permanently removed and cannot be recovered.

💡 Hint

Think about how versioning protects data from permanent deletion.

When versioning is enabled, deleting an object adds a delete marker. This hides the current version but keeps all previous versions intact and recoverable.

❓ Architecture

intermediate

How to configure S3 versioning for data protection in a multi-region setup?

You want to protect your data in an S3 bucket with versioning and replicate all versions to another region. Which AWS feature must you enable alongside versioning?

A Enable S3 Transfer Acceleration to speed up replication.

B Use Lifecycle policies to move versions to Glacier.

C Enable Cross-Region Replication (CRR) with versioning enabled on both buckets.

D Enable S3 Event Notifications to trigger Lambda for copying objects.

💡 Hint

Replication of versions requires a specific S3 feature that works with versioning.

Cross-Region Replication (CRR) replicates all versions of objects automatically between buckets in different regions when versioning is enabled on both.

❓ security

advanced

What is the effect of disabling versioning on an existing versioned S3 bucket?

You have a versioned S3 bucket with many object versions. You disable versioning on this bucket. What happens to the existing versions and new uploads?

A All existing versions are deleted immediately, and new uploads create versions.

B Existing versions remain, but new uploads overwrite objects without creating versions.

C Versioning is paused; new uploads create delete markers instead of versions.

D Existing versions are archived, and new uploads are rejected until versioning is re-enabled.

💡 Hint

Consider what disabling versioning means for existing data and future uploads.

Disabling versioning stops new versions from being created, but all existing versions remain intact and accessible.

✅ Best Practice

advanced

How to minimize storage costs while using S3 versioning for critical data?

You use S3 versioning to protect critical data but want to reduce storage costs over time. Which approach is best?

A Apply Lifecycle rules to transition non-current versions to cheaper storage classes like Glacier.

B Manually delete old versions every month to save space.

C Disable versioning and rely on backups instead.

D Use S3 Transfer Acceleration to reduce storage costs.

💡 Hint

Think about automated ways to manage old versions cost-effectively.

Lifecycle rules can automatically move older versions to cheaper storage classes, reducing costs while keeping data protected.

🧠 Conceptual

expert

What is the total number of object versions after these operations in a versioned S3 bucket?

In a versioned S3 bucket, you perform these steps on an object named report.pdf:

1. Upload report.pdf (version 1)
2. Upload a new report.pdf (version 2)
3. Delete report.pdf
4. Upload report.pdf again (version 3)

How many versions (including delete markers) exist for report.pdf now?

A 2 versions

B 3 versions

C 5 versions

D 4 versions

💡 Hint

Remember that deleting adds a delete marker version.

There are 3 uploads (versions 1, 2, and 3) plus 1 delete marker from the delete operation, totaling 4 versions.

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