EventBridge works with AWS CloudTrail. CloudTrail captures API calls made by or on behalf of your AWS account from the EventBridge console and to EventBridge API operations. Using the information collected by CloudTrail, you can determine what request was made to EventBridge, the IP address from which the request was made, who made the request, when it was made, and more. Alternatively consider using CloudWatch to log you EventBridge activity. For example, setup a new rule that will match all events and as the target define a CloudWatch Log Group. When events are now raised the rules will be captured to the log group. This may be enough to start the debugging exercise and get some insight into what is going on.
AWS documentation also has the following Troubleshooting Amazon EventBridge which may offer some additional avenues to explore.
Answering this for posterity.
CloudTrail provided the answer. In my case the IAM permissions were incorrect. The role used by the EventBridge Rule didn't allow the
codebuild:StartBuild action for the CodeBuild project name. In a previous CFN update, I had updated the name of the CodeBuild project but forgot to update the project name in the IAM rule.
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Why is my EventBridge Rule silently failing every week?Accepted Answerasked 9 months ago
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