Which combination of steps should the Administrator take to troubleshoot this issue?
(Choose three.)
Confirm that the EC2 instance’s security group authorizes S3 access.
Verify that the KMS key policy allows decrypt access for the KMS key for this IAM principle.
Check the S3 bucket policy for statements that deny access to objects.
Confirm that the EC2 instance is using the correct key pair.
Confirm that the IAM role associated with the EC2 instance has the proper privileges.
Confirm that the instance and the S3 bucket are in the same Region.
Explanations:
The security group associated with an EC2 instance controls inbound and outbound traffic to the instance, but it does not directly impact access to S3 resources. S3 access is controlled by IAM policies, bucket policies, and possibly KMS key policies. Therefore, this step is not relevant to the 403 Access Denied error.
If the S3 bucket is using server-side encryption with a KMS key, the IAM role must have permission to use that key. If the KMS key policy does not grant the necessary permissions to the IAM role, it would result in an access denied error when attempting to access the S3 bucket. Thus, verifying the KMS key policy is essential.
An S3 bucket policy can explicitly deny access to certain users or roles. If there are statements within the bucket policy that deny access to the objects for the IAM role associated with the EC2 instance, it would cause an HTTP 403 error. Therefore, checking the S3 bucket policy for deny statements is necessary for troubleshooting.
The key pair associated with the EC2 instance is used for SSH access to the instance and does not affect the permissions or access to AWS services like S3. The 403 error is related to IAM policies, S3 bucket policies, or KMS permissions, not the key pair used to access the instance.
The IAM role associated with the EC2 instance must have the appropriate permissions to access the S3 bucket and its objects. If the role does not include the necessary permissions (such ass3:GetObject), this would lead to an HTTP 403 error when the application attempts to access S3 resources. Therefore, confirming the IAM role’s permissions is critical.
While it is generally good practice to keep resources within the same region for performance reasons, AWS S3 is a global service. A 403 Access Denied error is not caused by the S3 bucket and EC2 instance being in different regions. Access issues are typically due to IAM permissions or bucket policies, not the region configuration.
Based on what I know, the answer is:
Verify that the KMS key policy allows decrypt access for the KMS key for this IAM principle.