Using Network Flow Monitor

Network Flow Monitor provides near real-time visibility into network performance, such as packet loss and latency, for traffic between Amazon EC2 instances, as well as traffic toward other AWS services, such as Amazon S3 and Amazon DynamoDB. Network Flow Monitor receives data from lightweight software agents that you install on your instances. The agents gather performance statistics from TCP connections. This data is sent to the Network Flow Monitor backend service, and the top contributors for each metric type are calculated. Network Flow Monitor also determines if AWS is the cause of a detected network issue, and reports that information for network flows that you choose to monitor details for.

Network Flow Monitor is intended for network operators and application developers who want near real-time insights into network performance. In the Network Flow Monitor console in CloudWatch, you can see performance data for your resources' network traffic that has been aggregated from agents and grouped into different categories. For example, you can see data for flows between Availability Zones or between VPCs. Then, you can create monitors for specific flows that you want to see more details for and track more closely over time.

Using a monitor, you can quickly visualize packet loss and latency of your network connections over a time frame that you specify. For each monitor, Network Flow Monitor also generates a network health indicator (NHI). The NHI value informs you whether there were AWS network issues for the network flows tracked by your monitor during the time period that you're evaluating. Using the NHI information, you can quickly decide whether to focus troubleshooting efforts on an AWS network issue or network problems originating with your workloads.