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Capabilities of Azure Network Watcher

Azure Network Watcher provides monitoring and diagnostic capabilities for Azure network resources. It enables you to monitor, diagnose, and view metrics for your virtual machines, network interfaces, virtual networks, load balancers, and other network components.

Key Capabilities

IP Flow Verify

IP Flow Verify allows you to test whether a virtual machine can send or receive traffic to or from a specific IP address. This is crucial for diagnosing security group or user-defined route configurations that might be blocking traffic.

How it works:

• You specify the direction of traffic (inbound or outbound), protocol, source/destination IP address, and port.
• Network Watcher analyzes the effective network security group rules and user-defined routes applied to the VM's network interface.
• It returns whether the traffic is allowed or denied and the specific rule causing the action.

Next Hop

The Next Hop feature helps you diagnose network routing issues by identifying the next hop for traffic originating from a virtual machine to a specified destination. This is essential for understanding how User Defined Routes (UDRs) and system routes affect traffic flow.

Information provided:

• The type of next hop (e.g., Internet, Virtual Network Gateway, VNetLocal).
• The IP address of the next hop.
• The routing type (System or Custom).

Security Group View

Security Group View allows you to view the effective security rules applied to a virtual machine. This helps you understand which rules are currently active and potentially blocking traffic.

• Displays both inbound and outbound effective security rules.
• Shows rules from all applied Network Security Groups (NSGs).
• Helps identify rule conflicts or unintended blocking.

Connection Monitor

Connection Monitor is a powerful tool for monitoring network connectivity between endpoints. It can monitor the reachability of specific ports and protocols between a source and a destination.

• Configurable monitoring of network paths.
• Detects network performance issues, such as latency and packet loss.
• Supports monitoring across different Azure regions and on-premises locations.

Packet Capture

Packet Capture enables you to capture network traffic to and from an Azure virtual machine. This is invaluable for deep packet inspection and troubleshooting complex network issues.

• Capture traffic to a PCAP file.
• Configure capture filters based on IP address, port, and protocol.
• Specify capture buffer size and duration.

Network Security Group (NSG) Flow Logs

NSG Flow Logs provide visibility into IP traffic flowing through your Network Security Groups. They record information about the IP traffic that passes through an NSG.

• Record traffic to a storage account.
• Analyze traffic patterns, identify security threats, and optimize network performance.
• Data is collected at 1-minute intervals.

Topology

Network Watcher's Topology feature provides a visual representation of your virtual network resources, including virtual machines, virtual networks, subnets, and load balancers, and their connections.

• Visualize the network infrastructure.
• Understand dependencies between resources.
• Facilitate network troubleshooting and planning.

Resource Usage Statistics

This feature provides statistics for network resources, such as the number of active connections to a load balancer or the traffic volume for a virtual machine's network interface.

Diagnose and Solve Network Problems

This integrated experience within Network Watcher guides you through common network troubleshooting scenarios, offering step-by-step diagnostics and solutions.