S3 versioning in AWS - Commands & Configuration

Introduction

Sometimes files in storage get overwritten or deleted by mistake. S3 versioning helps keep all versions of files so you can recover old ones if needed.

When you want to protect important files from accidental deletion or overwriting.

When you need to keep a history of changes to files stored in S3.

When multiple people or systems update files and you want to track each change.

When you want to recover a previous version of a file after a mistake.

When you want to audit changes to files over time.

Commands

This command creates a new S3 bucket named 'example-versioned-bucket' in the us-east-1 region where we will enable versioning.

Terminal

aws s3api create-bucket --bucket example-versioned-bucket --region us-east-1

Expected Output

No output (command runs silently)

→

--bucket - Specifies the name of the bucket to create.

→

--region - Specifies the AWS region where the bucket will be created.

This command turns on versioning for the bucket so that all changes to files are saved as different versions.

Terminal

aws s3api put-bucket-versioning --bucket example-versioned-bucket --versioning-configuration Status=Enabled

Expected Output

No output (command runs silently)

→

--bucket - Specifies which bucket to enable versioning on.

→

--versioning-configuration - Sets the versioning status to Enabled.

This command checks the versioning status of the bucket to confirm it is enabled.

Terminal

aws s3api get-bucket-versioning --bucket example-versioned-bucket

Expected Output

{"Status": "Enabled"}

→

--bucket - Specifies which bucket to check.

This command uploads a file named file.txt to the bucket. Each upload creates a new version if versioning is enabled.

Terminal

aws s3 cp file.txt s3://example-versioned-bucket/file.txt

Expected Output

upload: ./file.txt to s3://example-versioned-bucket/file.txt

→

cp - Copies a file to the S3 bucket.

This command lists all versions of the file.txt in the bucket so you can see the different saved versions.

Terminal

aws s3api list-object-versions --bucket example-versioned-bucket --prefix file.txt

Expected Output

{"Versions": [{"Key": "file.txt", "VersionId": "111111111111111111111", "IsLatest": true, "LastModified": "2024-06-01T12:00:00.000Z"}]}

→

--bucket - Specifies the bucket to list versions from.

→

--prefix - Filters the list to only show versions of file.txt.

Key Concept

If you remember nothing else from this pattern, remember: enabling versioning on an S3 bucket saves every change to files so you can recover old versions anytime.

Common Mistakes

Trying to enable versioning on a bucket that does not exist.

The command will fail because versioning can only be enabled on existing buckets.

First create the bucket, then enable versioning.

Assuming versioning is enabled by default on new buckets.

Versioning is off by default, so changes will overwrite files without saving old versions.

Always explicitly enable versioning after creating the bucket.

Uploading files without checking versioning status.

If versioning is not enabled, uploads overwrite files without keeping history.

Check versioning status with get-bucket-versioning before uploading important files.

Summary

Create an S3 bucket to store your files.

Enable versioning on the bucket to save all changes as versions.

Upload files to the bucket; each upload creates a new version.

List object versions to see all saved versions of a file.

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