What is the MOST likely reason that the Business-Unit tag is absent?
The Business-Unit tag is not activated as a cost allocation tag in the AWS Billing and Cost Management console.
The Business-Unit tag is not valid because tag key names do not support dashes (-).
The instances have been rebooted, and the developers neglected to re-add the Business-Unit tag after the reboot.
The IAM user does not have permission to view the tags in Cost Explorer.
Explanations:
Cost allocation tags must be activated in the AWS Billing and Cost Management console for them to appear in Cost Explorer. Without activation, tags cannot be used to filter or group cost data.
Dashes (-) are valid characters in tag keys, so the format of the tag keyBusiness-Unitis not an issue.
Rebooting instances does not remove tags; tags persist across instance reboots.
Tag visibility in Cost Explorer does not depend on specific IAM permissions. If the tag is not activated as a cost allocation tag, it will not appear in Cost Explorer, regardless of permissions.
From what I’ve heard, the answer is:
The Business-Unit tag is not activated as a cost allocation tag in the AWS Billing and Cost Management console.
In my opinion, the answer is:
The Business-Unit tag is not activated as a cost allocation tag in the AWS Billing and Cost Management console.