How should this be accomplished?
Enable flow logs on the NAT gateway elastic network interface and use Amazon CloudWatch insights to filter data based on the source IP addresses.
Run an AWS Cost and Usage report and group the findings by instance ID.
Use the VPC traffic mirroring feature to send traffic to Amazon QuickSight.
Use Amazon CloudWatch metrics generated by the NAT gateway for each individual instance.
Explanations:
Enabling flow logs on the NAT gateway’s elastic network interface allows you to capture network traffic, including the source IP addresses of instances. Using Amazon CloudWatch Insights, you can then filter the data based on these source IP addresses to identify which instances are generating the most traffic.
AWS Cost and Usage reports track costs, but they don’t provide detailed information about which specific instances are generating the traffic. This option would not help in identifying which instances are creating the most network traffic.
VPC traffic mirroring is used for deep packet inspection and security analysis, but it’s not designed for identifying high network usage per instance. Sending the traffic to Amazon QuickSight would not provide a direct or effective way to pinpoint high-traffic instances.
While CloudWatch metrics for the NAT gateway can provide overall data transfer statistics, it does not break down usage by individual instances. This method won’t help identify which specific instances are generating the most traffic.