AWS part →13 Bucket Versioning and cross region Replication

7 min readMay 11, 2023



What is Bucket Versioning in S3 →

Bucket versioning in Amazon S3 is a feature that allows you to keep multiple versions of an object (file) within a bucket.

  1. Normally, when you upload a new version of a file to S3, it replaces the existing file. However, with bucket versioning enabled, instead of replacing the file, S3 creates a new version of it and keeps track of all the different versions.
  2. Imagine you have a bucket in S3 and you upload a file called “example.txt” to it. Later, you make some changes to the file and upload it again with the same name. Without versioning, the original file would be overwritten, and you would lose the previous version. But with versioning enabled, S3 stores both versions of the file.
  3. Each version of the file in S3 is assigned a unique identifier, called a version ID. You can think of it as a label that distinguishes one version from another. So now, you have two versions of “example.txt” in your bucket, each with its own version ID.
  4. Bucket versioning provides several benefits. Firstly, it allows you to preserve all versions of an object, which can be useful for auditing purposes or if you need to revert to a previous version of a file. Secondly, it helps protect your data against accidental deletions or overwrites, as every version is retained. If you delete a file, S3 will mark it as a delete marker, but the actual data remains available with its version history intact.
  5. You can manage bucket versioning through the S3 management console, SDKs (software development kits), or API (application programming interface) calls. You can retrieve specific versions of objects by specifying the version ID, and you can also list all the versions of an object within a bucket.

However, it’s important to note that enabling bucket versioning can increase storage costs, as each version of an object consumes storage space. So you should carefully consider the storage requirements and cost implications before enabling versioning on your S3 bucket.

What is Multifactor Authentication In S3

Multifactor authentication (MFA) in Amazon S3 is a security feature that adds an extra layer of protection to your S3 bucket. It ensures that only authorized individuals with the correct credentials can access and modify your bucket’s contents.

  1. To understand MFA, let’s first talk about regular authentication. When you access your S3 bucket, you typically use a username and password. This single-factor authentication relies solely on something you know (your password) to verify your identity. However, passwords can be stolen, guessed, or compromised, putting your data at risk.
  2. MFA enhances security by introducing a second factor, which is something you possess, in addition to the password. This second factor is usually a physical device called an MFA device or app, which generates a unique code that changes periodically.
  3. Here’s how it works with S3 and MFA enabled: When you try to perform certain actions that require high-level permissions, such as deleting objects or changing bucket settings, S3 prompts you to enter an additional code from your MFA device. This code is only valid for a short period, usually 30 seconds, and is synchronized with the authentication server.
  4. To complete the authentication process, you must enter the correct code from your MFA device along with your regular username and password. This ensures that even if someone has your password, they cannot access your S3 bucket without the corresponding code from your MFA device.
  5. MFA adds an extra layer of security because it combines something you know (password) with something you possess (MFA device). Even if an attacker somehow obtains your password, they would still need physical possession of your MFA device or app to generate the correct code.
  6. Enabling MFA for your S3 bucket can help prevent unauthorized access, accidental deletions, or modifications to your data. It’s especially important for buckets containing sensitive or critical information.

To set up MFA for your S3 bucket, you need to associate an MFA device with your AWS (Amazon Web Services) account and then enable MFA for the desired IAM (Identity and Access Management) user or root account. Once enabled, whenever you perform high-level actions in S3, you’ll be prompted to provide the current code from your MFA device in addition to your regular credentials.

what is multiport upload

The term “multiport upload” is not a standard feature in Amazon S3. It appears to be a misinterpretation or incorrect terminology.

  1. In Amazon S3, the primary method of uploading objects (files) to a bucket is through the use of PUT requests, which involve sending the entire object in a single operation. This is commonly referred to as a single-part upload.
  2. On the other hand, multipart upload is a feature provided by Amazon S3 that allows you to upload large objects in smaller parts. It is particularly useful for files that are several gigabytes or terabytes in size. Instead of uploading the entire object in one go, you can break it down into smaller parts and upload them concurrently.
  3. Multipart upload offers several advantages. Firstly, it improves reliability. If a part fails to upload, you only need to re-upload that specific part instead of the entire object. Secondly, it enables parallel uploading, which can significantly speed up the upload process for large files. Additionally, it allows you to pause, resume, or abort an upload, giving you more control and flexibility.
  4. When using multipart upload, you split the object into smaller parts, typically ranging from 5 MB to 5 GB in size. Each part is uploaded separately, and once all parts are uploaded, you can combine them to create the complete object. Amazon S3 takes care of managing and organizing the individual parts for you.
  5. Multipart upload can be performed programmatically using the AWS SDKs (software development kits), command-line tools, or API (application programming interface) calls. Some third-party tools and applications also support multipart upload for Amazon S3.

By utilizing multipart upload, you can efficiently upload large files to Amazon S3, ensuring reliability, speed, and control over the upload process.

Cross region replication or copying of S3 objects →

Cross-region replication in Amazon S3 is a feature that allows you to automatically and asynchronously copy your S3 objects (files) from one region to another. It provides a convenient way to have data redundancy and ensures that your objects are stored in multiple regions for improved durability and availability.

Here’s how cross-region replication works in easy language:

  1. Enable Cross-Region Replication: You start by enabling cross-region replication for your S3 bucket. You specify the source region (where the objects currently reside) and the destination region (where you want the objects to be replicated).
  2. Replication Configuration: In the replication configuration, you define the rules that specify which objects to replicate and where to replicate them. You can choose to replicate all objects or only those that match certain prefixes or tags.
  3. Replication Process: Once the replication configuration is set up, S3 automatically monitors the source bucket for any new objects or changes to existing objects. When it detects a change, it asynchronously replicates the object to the destination region.
  4. Replication Metadata: When an object is replicated, S3 adds some metadata to the replicated object to indicate its origin. This metadata helps you identify replicated objects and distinguish them from the original objects.
  5. Replication Time: The time it takes for an object to be replicated depends on the size of the object, the network conditions, and the availability of resources. It’s important to note that replication is asynchronous, meaning it happens in the background, so there may be a slight delay between changes in the source bucket and their replication to the destination bucket.

By utilizing cross-region replication, you gain several benefits:

  • Disaster Recovery: If an unforeseen event affects one region, you still have a copy of your objects in another region, ensuring data resilience and minimizing downtime.
  • Reduced Latency: By placing copies of your objects closer to your users in different regions, you can reduce the latency (delay) experienced by users accessing your objects.
  • Compliance and Data Sovereignty: Cross-region replication allows you to meet data residency and compliance requirements by replicating objects to specific regions that adhere to specific regulations or data sovereignty laws.
  • It’s important to consider that enabling cross-region replication incurs additional costs, as you will be charged for data transfer between regions and storage in the destination region. Therefore, it’s essential to evaluate the cost implications and choose replication strategies based on your specific needs.

Overall, cross-region replication provides a robust mechanism for automatically copying and synchronizing your S3 objects across different regions, enhancing data durability, availability, and compliance.




Cloud computing and DevOps Engineer and to be as a fresher I am learning and gaining experiance by doing some hands on projects on DevOps and in AWS OR GCP