Azure Network Watcher provides tools to monitor, diagnose, view metrics, and enable or disable logs for resources in an Azure virtual network.
Capture packets to and from a VM
Advanced filtering options and fine-tuned controls, such as the ability to set time and size limitations, provide versatility. The capture can be stored in Azure Storage, on the VM's disk, or both. You can then analyze the capture file using several standard network capture analysis tools.
Network Watcher variable packet capture allows you to create packet capture sessions to track traffic to and from a virtual machine. Packet capture helps to diagnose network anomalies both reactively and proactivity.
Reference:
https://docs.microsoft.com/en-us/azure/network-watcher/network-watcher-monitoring-overview