The replication is configured to be one-directional from the source bucket "Bucket-1" to the destination bucket "Bucket-2".
Start by navigating to "Bucket-1". Then under Management, select Create replication rule.
Choose the rule name, and keep the Status as Enabled. An enabled rule starts working once this rule is saved.
Make sure to apply the rule to all the objects in the source bucket by selecting Apply to all objects in the bucket. Then choose the destination “Bucket-2” using Browse S3.
It is mandatory for buckets replication to enable Versioning. If it is not enabled beforehand, the AWS console shows a banner where you can click and enable for both source and destination. examples below:
Source Bucket
Destination Bucket
For IAM role, select Create new role from the dropdown list.
It is recommended to choose Create new role rather than choosing an existed IAM role. Once the replication rule is saved, AWS S3 creates a new IAM role and generates a new policy that matches the configuration of the source and destination buckets.
You must enable Replicate objects encrypted with AWS KMS. This is required since the encryption is enabled on the source bucket.
Since this is a cross-region-replication, you need to choose the AWS KMS key for decrypting source objects, make sure to select the correct one, selected in the previous section. Then choose a key on the destination region to re-encrypt the objects.
For this practice all the keys used are AWS KMS managed keys, you can always create or bring your custom key.
Save the rule, and with this replication is configured.