When you need to check the average round-trip time of packets between two Azure virtual machines, which feature in Azure Network Watcher should you utilize?

Using Connection Monitor is the appropriate choice for checking the average round-trip time of packets between two Azure virtual machines. This feature is specifically designed to monitor the availability of your resources and to provide insights into network performance metrics, such as round-trip times and latency between the endpoints. By leveraging Connection Monitor, you can set up the necessary tests to continuously measure network connectivity and performance, and you can easily gain visibility into the network path, helping to identify any issues impacting connectivity or performance between your VMs.

Other features offered by Azure Network Watcher serve different purposes. For example, IP flow verify is primarily used for troubleshooting traffic flow issues by determining if a packet would be allowed or denied by any configured network security group (NSG) rules. Connection troubleshoot provides insights on connectivity issues but does not specifically measure round-trip times. NSG flow logs provide detailed information about the traffic that flows through the NSGs, but they do not give real-time metrics on latency or round-trip time. Therefore, for the specific requirement of measuring average round-trip time, Connection Monitor is the most effective tool in Azure Network Watcher's suite of features.