Object versioning in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Object Versioning in Google Cloud Storage?

Object Versioning is a feature that keeps multiple versions of an object in a storage bucket. When enabled, every time you overwrite or delete an object, the old version is saved and can be restored later.

beginner

How does enabling Object Versioning help protect data?

It protects data by keeping previous versions of objects. If you accidentally delete or overwrite a file, you can recover the older version instead of losing it permanently.

intermediate

What happens when you delete an object in a bucket with Object Versioning enabled?

The object is not permanently deleted. Instead, a 'delete marker' is added, and the old versions remain stored. You can restore the object by removing the delete marker or accessing previous versions.

beginner

How do you enable Object Versioning on a Google Cloud Storage bucket?

You enable it by setting the bucket's versioning configuration to 'enabled' using the Cloud Console, gsutil command, or API. For example, with gsutil: `gsutil versioning set on gs://your-bucket-name`.

beginner

What is a practical example of using Object Versioning?

Imagine you have a photo album stored in a bucket. If you accidentally overwrite a photo, Object Versioning lets you restore the original photo from an earlier version, preventing data loss.

What does Object Versioning do in Google Cloud Storage?

A Keeps multiple versions of objects when they are changed or deleted

B Deletes objects permanently immediately

C Compresses objects to save space

D Encrypts objects automatically

Object Versioning keeps old versions of objects so you can recover them if overwritten or deleted.

How can you enable Object Versioning on a bucket?

A By uploading a special file

B By setting the bucket's versioning configuration to 'enabled'

C By deleting the bucket

D By changing the bucket's location

You enable Object Versioning by setting the bucket's versioning to 'enabled' via console, gsutil, or API.

If you delete an object in a versioned bucket, what happens?

A A delete marker is added and old versions remain

B The object is permanently removed immediately

C The bucket is deleted

D The object is moved to another bucket

Deleting an object adds a delete marker; previous versions are kept for recovery.

Why is Object Versioning useful?

A It reduces storage costs

B It speeds up file uploads

C It helps recover accidentally deleted or overwritten files

D It automatically backs up your entire project

Object Versioning helps recover files by keeping older versions.

Which command enables Object Versioning using gsutil?

A gsutil enable version gs://bucket-name

B gsutil set versioning true gs://bucket-name

C gsutil bucket version on

D gsutil versioning set on gs://bucket-name

The correct gsutil command is `gsutil versioning set on gs://bucket-name`.

Explain what Object Versioning is and how it helps protect data in Google Cloud Storage.

Think about how saving old copies of files can prevent data loss.

Describe the steps to enable Object Versioning on a Google Cloud Storage bucket.

Consider the tools you can use to change bucket settings.

Practice

1. What is the main purpose of enabling Object Versioning in a Google Cloud Storage bucket?

easy

A. To keep multiple versions of an object to recover from accidental deletion or overwrite

B. To increase the storage capacity of the bucket automatically

C. To encrypt objects with a stronger encryption key

D. To restrict access to objects based on user roles

Solution

1. Step 1: Understand Object Versioning concept

   Object Versioning allows storing multiple versions of the same object in a bucket.

2. Step 2: Identify the main benefit

   This helps recover previous versions if an object is deleted or overwritten by mistake.

3. Final Answer:

   To keep multiple versions of an object to recover from accidental deletion or overwrite -> Option A

4. Quick Check:

   Object Versioning = Data recovery [OK]

Hint: Versioning means saving old copies to recover later [OK]

Common Mistakes:

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

2. Which of the following commands correctly enables Object Versioning on a Google Cloud Storage bucket named my-bucket?

easy

A. gsutil versioning set on my-bucket

B. gsutil versioning enable gs://my-bucket

C. gsutil versioning set enabled gs://my-bucket

D. gsutil versioning set on gs://my-bucket

Solution

1. Step 1: Recall gsutil syntax for enabling versioning

   The correct command is gsutil versioning set on gs://bucket-name.

2. Step 2: Match the command to the bucket name

   gsutil versioning set on gs://my-bucket matches the correct syntax and bucket name format.

3. Final Answer:

   gsutil versioning set on gs://my-bucket -> Option D

4. Quick Check:

   Enable versioning = gsutil versioning set on [OK]

Hint: Use 'gsutil versioning set on gs://bucket' to enable [OK]

Common Mistakes:

• Omitting 'gs://' prefix
• Using 'enable' instead of 'set on'
• Adding extra words like 'enabled'

3. Consider a bucket with Object Versioning enabled. If you upload a file named report.txt three times with different content, how many versions of report.txt will exist in the bucket?

medium

A. 3

B. 1

C. 2

D. 4

Solution

1. Step 1: Understand versioning behavior on multiple uploads

   Each upload creates a new version if versioning is enabled.

2. Step 2: Count versions after three uploads

   Uploading three times creates three distinct versions of the same object.

3. Final Answer:

   3 -> Option A

4. Quick Check:

   Uploads = Versions when versioning on [OK]

Hint: Each upload creates a new version if versioning is enabled [OK]

Common Mistakes:

• Assuming only one version exists
• Counting versions as uploads minus one
• Confusing versions with copies

4. You enabled Object Versioning on a bucket but notice that old versions are not visible when listing objects. What is the most likely cause?

medium

A. Old versions are automatically deleted after 24 hours

B. Versioning was not actually enabled on the bucket

C. You used gsutil ls which only shows live versions by default

D. You need to enable versioning on each object separately

Solution

1. Step 1: Understand default listing behavior

   By default, gsutil ls shows only the current live versions, not older ones.

2. Step 2: How to list all versions

   Use gsutil ls -a to see all versions including old ones.

3. Final Answer:

   You used gsutil ls which only shows live versions by default -> Option C

4. Quick Check:

   Default list hides old versions [OK]

Hint: Use 'gsutil ls -a' to see all versions [OK]

Common Mistakes:

• Assuming versioning not enabled without checking
• Believing old versions auto-delete quickly
• Thinking versioning applies per object

5. You want to keep only the latest 5 versions of objects in a bucket with Object Versioning enabled to save storage costs. Which approach should you use?

hard

A. Disable Object Versioning and re-enable it every month

B. Set a lifecycle rule to delete noncurrent versions older than a certain age

C. Manually delete old versions using the Cloud Console every week

D. Rename objects to avoid creating new versions

Solution

1. Step 1: Understand lifecycle management for versioned objects

   Lifecycle rules can automatically delete old versions based on age or count.

2. Step 2: Choose the best automated approach

   Setting a lifecycle rule to delete noncurrent versions older than a set time saves costs without manual work.

3. Final Answer:

   Set a lifecycle rule to delete noncurrent versions older than a certain age -> Option B

4. Quick Check:

   Use lifecycle rules to manage old versions [OK]

Hint: Use lifecycle rules to auto-delete old versions [OK]

Common Mistakes:

• Relying on manual deletion which is error-prone
• Disabling versioning loses all version history
• Renaming objects does not control version count