S3 Bucket Cross-Region Replication Rule
This rule ensures cross-region replication is enabled for S3 buckets.
| Rule | S3 bucket cross-region replication should be enabled |
| Framework | NIST Cybersecurity Framework (CSF) v1.1 |
| Severity | ✔ Critical |
Rule: S3 Bucket Cross-Region Replication for NIST Cybersecurity Framework
S3 Bucket Cross-Region Replication (CRR) is a critical feature for enhancing the resilience and redundancy of your data storage on AWS. Adhering to the NIST Cybersecurity Framework (CSF) v1, enabling CRR helps meet the Recover (RS) function by allowing for quick restoration of data after a disruption.
Description of S3 Cross-Region Replication
Cross-Region Replication (CRR) is an Amazon S3 feature that automatically replicates data from one S3 bucket to another S3 bucket in a different AWS region. This is crucial for disaster recovery scenarios and helps meet compliance requirements. CRR is managed at the bucket level and includes the following features:
- Replication of new objects automatically
- Replication of object deletions, if configured
- Maintenance of object metadata and ACLs
- Optional replication of existing objects
Troubleshooting Steps for CRR
Verify Replication Configuration
- 1.Check if CRR is enabled on the source bucket.
- 2.Ensure the destination bucket exists in a different region.
- 3.Confirm the correct IAM roles and permissions are in place for replication.
- 4.Review the replication configuration to include the desired objects or prefixes.
Check Replication Status
- 1.Verify that the object's replication status is "Completed" in the source bucket.
- 2.In case of failure, the status will be "Failed" – inspect the S3 replication metrics in the AWS Management Console for errors.
Review IAM Policies and Bucket Policies
- 1.Cross-check the IAM roles and policies to ensure they have the
,s3:GetReplicationConfiguration
, ands3:ListBucket
permissions for the corresponding buckets.s3:PutObject - 2.Ensure the bucket policy on the destination bucket permits the source bucket to replicate objects.
Necessary Codes
IAM Role for Replication
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:GetReplicationConfiguration",
"s3:ListBucket"
],
"Resource": [
"arn:aws:s3:::source-bucket"
]
},
{
"Effect": "Allow",
"Action": [
"s3:ReplicateObject",
"s3:ReplicateDelete",
"s3:ReplicateTags"
],
"Resource": "arn:aws:s3:::destination-bucket/*"
}
]
}
Enabling CRR Using AWS CLI
aws s3api put-bucket-replication --bucket source-bucket-name --replication-configuration file://replication.json
Where
replication.jsonStep by Step Guide for Remediation
Step 1: Verify Prerequisites
- Source and destination buckets must have versioning enabled.
- The source bucket must have the proper permissions set up.
Step 2: Establish IAM Roles for Replication
- Create an IAM role with the necessary permissions to perform replication actions.
Step 3: Configure Cross-Region Replication
- Use the AWS Management Console or AWS CLI to enable and configure CRR on the source bucket.
Step 4: Monitor Replication
- Regularly check the S3 replication metrics and logs for successful replication activities and troubleshoot any issues.
Step 5: Test the Configuration
- Perform a test upload to the source bucket and confirm that it is replicated to the destination bucket accurately.
By following these steps and ensuring proper configuration, S3 CRR will be in compliance with the NIST CSF for improved data resiliency.