Chapter 5 of this blog post series will be all about Amazon’s object-based storage service, S3 and the Cross Region Replication.
S3 Cross Region Replication
For cross region S3 Replication, versioning for the S3 bucket must be enabled.
You can replicate all contents in the bucket or only a specific prefix.
Buckets in this AWS account or buckets in a different bucket.
Change the storage class tier for the replicated object(s):
- S3 Standard
- S3 Standard Infrequently Accessed (IA)
- S3 Reduced Redundancy Storage (RRS)
You can manually copy objects from one S3 Region to another using the AWS CLI.
aws cli s3 cp --recursive s3://cdhubhubsamplebucketREGION1 s3://cdubhubsamplebucketREGION2
ONLY NEW OBJECTS PLACED IN THE BUCKET ARE REPLICATED. Anything existing is not replicated until it is updated / changed.
- Permissions DO NOT replicate across when performing a cross site copy from one bucket to another bucket.
- Permissions DO replicate across when performing a cross site replication for a new object from one bucket to another.
- When you delete files from one bucket the deletion marker is replicated across but then if you delete the delete marker on the source, the delete marker is NOT deleted on the replica object.
- Versioning must be enabled on both the source and destination buckets
- Regions must be unique – you cannot replicate one bucket to another bucket in the same region using cross region replication, you can however use the copy command
- Files in an existing bucket are not replicated automatically. All subsequent updated files will be replicated automatically
- You cannot replicate to multiple buckets or use daisy chaining
- Delete markers are replicated.
- Deleting individual versions or delete markers will not be replicated.
- For the exam a basic understanding of what cross region replication is required to pass the exam.