How do I confirm interface VPC endpoint usage?

Question

How can we validate or confirm that AWS PrivateLink is actually being used? I have an AWS Lambda function that sends logs to a third party using AWS PrivateLink and the logs aren't being received. Therefore, I'm not sure if PrivateLink is being used. There's no helpful logging with the function, and the setup is exactly the same across environments. Nothing in CloudTrail shows up, and the VPC Flow Logs show status on the ENIs as "NODATA".

agardezi · Accepted Answer

If VPC Flow Logs for the AWS Lambda ENI isn't showing any data going to the IP address of the ENI for AWS PrivateLink, then your traffic isn't going to the private link. The "NoData" status in your VP Flow Logs means no data was recorded during the five minute capture period that is set on the ENI. You can try inserting some extra debugging around the AWS Lambda code, which will make the function call to the logging API. The debugging code can also check the logging API configuration to make sure that it's configured to point to the AWS PrivateLink endpoint address.

How do I confirm interface VPC endpoint usage?

Relevant content