Cross-Region replication feature enables asynchronous automatic replication of copying objects between two AWS regions. You need to enable this feature on bucket level and configure on source bucket. This feature allows you to either select the whole source or subset of an object to replicate on destination region.

Important things to keep in mind:

· Cross-region will not work if versioning feature is not enabled on the bucket

· You cannot replicate bucket within the same region and hence it must be between two different regions

· Existing files within in the bucket are not replicated, when enabled cross-region feature. All the objects and subset which are created post enabling cross-region replication will be replicated.

· You cannot replicate the S3 bucket to the third region

· Objects which are marked as deleted are also replicated

Let’s do the LAB, we will create two S3 bucket called apmumbucket (source in Asia Pacific India region) & apsgbucket (destination in Asia Pacific Singapore region) and using the cross-region replication feature will replicate the object.

Go to the Amazon S3 console and create a new bucket

Create a bucket called apmumbucket and select the region Asia Pacific (Mumbai)

Versioning is must and hence we will enable it and proceed further

Enabling read permission here is not mandatory but just to access from internet I am selecting read permission, you can ignore this option

Review the settings and click on create bucket

Let us upload one file

Observe the file is uploaded in the bucket called apmumbucket

Let us now create another bucket in Singapore region where we want to replicate the content from Mumbai Region. Just review the summary as I am creating a bucket called apsgbucket

Now we can see both the buckets are created in cross-region (Mumbai & Singapore) & let’s enable the feature

Go to the bucket property of apmumbucket which is our source and look for the option cross-region replication

Enable it and verify the below settings:

· Source – Select Asia Pacific (Mumbai)

o Whole Bucket – Under this bucket we have the option to select the whole or sub buckets if available. We will select whole bucket

· Destination – Select Asia Pacific (Singapore)

o Bucket name – The bucket in which you want to replicate. We will select the one which we created apsgbucket

· Destination Storage Class – Type of storage class what we learned in previous article. Since this is the secondary or replica copy we will select infrequent access class.

· Role – Either it will create by default one for you or we can create our own. Will leave the default settings.

You can select other than whole bucket

You have the option to select different storage class

Now the cross-region replication is enabled

Let us see now if we can see anything under the bucket apsgbucket as we have uploaded one file as mentioned above. Any object prior to enabling the cross-region feature isn’t replicated.

Let us know try to upload a new file in bucket apmumbucket and see if it replicates on the bucket apsgbucket

Verify the settings and upload

File upload is successful in bucket apmumbucket, let us now quickly go to the bucket apsgbucket to see if the file is replicate or not.

The file now is automatically replicated

Also there is only one version of the file. Now let us download the file from bucket apmumbucket (APAC Mumbai region) and modify the content and upload another version. We will see if that is replicated too in Singapore region bucket

There is a file name called test file.txt, download the file and modify it. Save it and again upload it to the bucket apmumbucket

We see there are now two versions for the file test file.txt

Notice the same file replicate with the latest versions too 😀

In this article we will do LAB on AWS S3 Bucket & its Versioning. We will run through on how to create a S3 bucket and understand its permission so that we can delegate the right users to access what bucket they should access.

Also we will run through the feature called “Versioning” a powerful way in which you can protect the modification or deletion of the file. Versioning basically stores all versions of an object and consider it as one of the great backup tool. We will also go through the restoration process which is quite easy.

Go to the services dashboard and select S3 storage service

You will notice while creating a bucket it also asks for the region, I have selected my nearest region as Mumbai

You cannot use the name which is already been used as discussed in our previous article the bucket namespace is global and it must be unique. It seems mumbucket is already been created so let’s create bucket name called mumbucket1

If you notice mumbucket1 is created

Click on mumbucket1, on the right pane you will notice its attribute and values associated

As you see below storage management features are now available in new console, let’s click on Opt-In to do our further Lab step in new console

Below is the Amazon S3 new console look

After clicking on the mumbucket1, the features associated to the object will be displayed as mentioned below

Clicking on permission option shows who has access to the bucket and what kind of permission is assigned. Below is the default root permission which is applied when the bucket was created. You can add other AWS users or assign permission to everyone whom you want to allow access from internet.

Let us upload file and then assign permissions

Here is my file from the desktop called test.txt to upload

You can assign the permission here as who can access what, the root account that is Charles*** has permission by default and while uploading we can assign other users permissions too. The file will not be accessible from internet as it is private by default. Notice there are two types of permission and below is explanation.

· Object Permission – When you select read or write option the users has access not to read the document but to modify or delete.

· Object Permission – when you assign read or write the user will be able to view who all users have the permission to that particular object and can modify that permission too.

Let’s leave the default and click on next to continue

We have gone through the previous article on the storage class and their features for this particular lab we will leave default option and click on next to continue

Review the settings and click on upload

The file is uploaded in the bucket as mumbucket1

Click on the file test.txt and you will notice the link to access the file but when you try to access it throws access denied error because we had not assigned any permission to access from internet.

You can select option make public so that the file is accessible from internet

Now you see the permission is updated and AllUsers is updated with permission is set to read on Object access

Now when you open the test.txt file link again you will notice it is opening without any access denied error.

So far we have created a bucket called mumbucket1 and uploaded a test.txt file, let’s enable versioning on bucket and the file containing inside the bucket will have multiple version when changes are made to it. To enable the versioning all we have to do is under properties of the bucket enable the versioning radio button.

One thing you must be aware that once you enable the versioning you cannot disable it except suspend that means will going forward not keep multiple version of file once the versioning is suspended but which was already had different versions of file will be kept as it is. If you want to delete it, the process is to manually select the appropriate version which you want to delete.

Versioning is now enabled

Notice on top there is a tab called latest version, you can drop down for multiple version of a file.

Let us now download the test.txt file, modify the content and upload it

I have updated the file with next line – “updating the downloaded file”. Notice the file name must not be changed or you should not replace it with same name file.

Let’s set the file permission so that it can be accessible from the internet and upload it.

Now when you see the file properties and drop down the latest version tab you will notice there are two files. Remember it will double the size of the size in your S3 storage and you might want to consider before enabling versioning feature.

Now when you try to access the test.txt file link, notice the updated content inside the text file.

You can also select the respective versions and delete unwanted and let’s say we delete the latest version

The test.txt will be showing the original file as mentioned below.

Now let’s delete the test.txt file and try to restore it. Select the test.txt file and under more option select the delete option and the file will be deleted.

File is deleted now. I was going through the AWS technical documentation but was unable to find a guide on how to restore object from a new portal. For this lab we will be going back to old console of S3 storage service.

Now when you are on the old console select the bucket mumbucket1

You will notice versions: Hide / Show

Those files now which are deleted are actually marked as deleted not hard deleted. All we have to do is click on show and select the file which has a remark (delete marker) and through the action drop down select delete to move it from Show to Hide tab.

You will notice now the test.txt file has been restored successfully.

So far what we have learned:

· Creating a S3 bucket and checking its permission – very critical

· Securing S3 bucket using permission

· Enabling versioning on a bucket and checking multiple version of files

· Deleting and restoring file from the S3 bucket.