When you’re working with Azure networks, problems rarely announce themselves clearly. A VM can’t reach a service, traffic disappears, or performance suddenly drops.
Azure Network Watcher exists to give you visibility into what’s actually happening inside your network, instead of forcing you to guess.
Rather than being a single tool, Network Watcher is a collection of monitoring, diagnostic, and traffic analysis features that help you understand how your Azure network is built, how traffic flows through it, and why something might not be working. Used properly, it turns Azure networking from a black box into something you can reason about and troubleshoot with confidence.
Seeing the Big Picture with Network Topology
One of the first challenges in Azure is simply understanding what exists. Over time, virtual networks, subnets, gateways, firewalls, and peerings get added, and the overall shape of the network becomes hard to hold in your head.
Network Topology solves this by generating a visual map of your Azure network. It shows how virtual networks connect to each other, where subnets sit, and how resources are linked.
This is especially useful in environments that have grown organically or where multiple engineers have made changes over time. Instead of clicking through the portal resource by resource, you can see the full layout at a glance and quickly spot unexpected connections or missing components.
Monitoring Real Connectivity with Connection Monitor
Configuration alone doesn’t guarantee connectivity. A route might exist on paper, but traffic can still fail due to DNS, firewalls, or platform issues.
Connection Monitor lets you test and continuously monitor connectivity between endpoints. These endpoints can be Azure virtual machines, on-premises servers, or external services. Rather than just telling you that something is “up” or “down,” it measures latency, packet loss, and connection success over time.
This gives you early warning when a connection starts to degrade, not just when it completely fails.
For hybrid environments especially, this kind of end-to-end visibility is invaluable.
Understanding Why Traffic Is Blocked with IP Flow Verify
When traffic doesn’t flow, the first instinct is often to check network security groups.
But in Azure, multiple rules can apply at different levels, and it’s not always obvious which one is responsible.
IP Flow Verify allows you to test whether a specific packet would be allowed or denied. You specify the source, destination, port, and protocol, and Azure tells you whether the traffic is permitted.
More importantly, it tells you exactly which rule allowed or blocked it. This removes guesswork and speeds up troubleshooting dramatically, especially in locked-down environments.
Following the Route with Next Hop
Even if traffic is allowed, it still needs to be routed correctly. Azure networks can include user-defined routes, firewalls, gateways, and peering links, all of which influence where traffic goes.
Next Hop shows you the actual path traffic will take from a virtual machine to its destination.
It tells you whether traffic goes directly, through a virtual appliance, to the internet, or via a gateway. This makes it much easier to diagnose routing loops, misconfigured route tables, or traffic bypassing security controls when it shouldn’t.
Knowing the Real Security Rules with Effective Security Rules
Looking at a single network security group rarely tells the full story. A network interface can inherit rules from both its subnet and its own attached security group.
Effective security rules combines all applicable rules into one clear view.
It shows what rules are actually enforced on a network interface after Azure has evaluated priorities and inheritance.
This helps you understand the real security posture of a workload, rather than relying on assumptions based on individual rule sets.
Actively Testing with Connection Troubleshoot
Sometimes you don’t want to predict behavior, you want to test it directly. Connection Troubleshoot allows you to initiate a connectivity test between two Azure resources and see whether the connection succeeds.
If it fails, Azure provides diagnostic information explaining why. This is particularly useful when validating new deployments, checking firewall changes, or confirming that an application gateway or load balancer is reachable from the expected sources.
Capturing Traffic with Packet Capture
When higher-level tools aren’t enough, you may need to look at the traffic itself. Packet Capture lets you remotely capture packets from a virtual machine or virtual machine scale set without installing extra tools or logging into the VM.
This is useful for deep troubleshooting, protocol analysis, or validating application behaviour.
Because it’s controlled centrally through Azure, it’s also safer and easier to manage than traditional packet capture approaches in cloud environments.
Troubleshooting VPN Connections
Hybrid connectivity adds another layer of complexity. VPN gateways involve encryption, tunnels, routing, and on-premises dependencies.
VPN troubleshoot focuses specifically on diagnosing virtual network gateway issues.
It helps identify misconfigurations, tunnel problems, and connectivity failures between Azure and on-premises networks. For organizations relying on site-to-site or point-to-site VPNs, this tool can save hours of manual investigation.
Understanding Traffic at Scale with Flow Logs
Flow logs record metadata about IP traffic flowing through your Azure network. Instead of capturing packet contents, they log information such as source and destination IPs, ports, protocols, and whether traffic was allowed or denied.
These logs are stored in Azure Storage and form the foundation for deeper analysis.
They are essential for security auditing, compliance, and understanding long-term traffic patterns across your environment.
Turning Logs into Insight with Traffic Analytics
Raw logs are useful, but visual insight is better. Traffic analytics takes flow log data and turns it into dashboards and visualizations.
You can see which hosts communicate most frequently, where traffic enters and leaves the network, and where traffic is being denied.
Over time, this helps you identify unusual patterns, reduce unnecessary exposure, and make informed decisions about network design and security controls.
Why These Tools Matter
Azure networking is powerful, but complexity grows quickly as environments scale. Network Watcher tools give you visibility, confidence, and control.
They help you move from reacting to outages to understanding behaviour, validating design choices, and preventing issues before users notice them.
If you’re serious about running reliable, secure Azure networks, Network Watcher isn’t optional. It’s the difference between guessing and knowing what your network is really doing.