Monitoring .NET Core Applications with Application Insights

 

In today’s cloud-native world, building fast and scalable .NET Core applications is just one part of the job. The real challenge begins after deployment: How do you monitor performance, detect failures early, and keep your application healthy in real-time?

That’s where Azure Application Insights comes in.

In this guide, I’ll show you how to integrate Application Insights with your ASP.NET Core app, what you can monitor, and how to make the most of its powerful telemetry.

Whether you’re an indie developer, DevOps engineer, or architect — this is for you.

🚀 What is Application Insights?

Azure Application Insights is a powerful APM (Application Performance Management) tool that helps you:

✅ Detect application crashes and exceptions
✅ Track user behavior and requests
✅ Monitor response times and dependency calls
✅ Analyze bottlenecks with distributed tracing
✅ Correlate logs across services

It’s fully integrated with Azure Monitor, and it works seamlessly with .NET Core, .NET 6/7/8, Azure Functions, App Services, and even on-premise deployments.

🧰 Prerequisites

• A working ASP.NET Core application (any version from .NET Core 3.1+ to .NET 8)
• An Azure subscription (free tier works fine)
• Visual Studio / VS Code

🛠️ Step-by-Step: Integrate Application Insights in ASP.NET Core

1. Create Application Insights on Azure

• Go to Azure Portal → “Application Insights” → Create
• Choose your resource group, region, and name
• Copy the Instrumentation Key or Connection String

2. Add Application Insights NuGet Package

dotnet add package Microsoft.ApplicationInsights.AspNetCore

3. Configure in Program.cs (or Startup.cs)

builder.Services.AddApplicationInsightsTelemetry();

Or manually:

builder.Services.AddApplicationInsightsTelemetry("Your_Connection_String");

With just one line, your app now starts capturing telemetry data.

🔍 What Can You Monitor?

Head over to your Application Insights dashboard in Azure and explore:

✅ Live Metrics

Monitor real-time performance, requests, failures, and dependencies.

✅ Failures

See exception types, stack traces, and frequency breakdowns.

✅ Performance

Track response times of endpoints, dependencies, SQL queries, and more.

✅ Availability

Set global synthetic tests to ping your endpoints and report downtimes.

✅ User Sessions

Understand how users interact with your app, which pages they visit, and where they drop off.

🎯 Add Custom Events for Business Insights

_telemetryClient.TrackEvent("UserSubscribed", new Dictionary<string, string>
{
    { "Plan", "Enterprise" },
    { "UserId", "47832" }
});

You can now track business actions like subscriptions, signups, and upgrades — not just technical metrics.

📊 Query Logs with KQL (Kusto)

kql

requests
| where duration > 2s
| summarize count() by name

You can also correlate this with exception logs, page views, or dependency calls.

📦 Don’t Forget to Set Alerts

Set smart alerts like:

• “Exceptions > 5 in 10 minutes
• “Response time > 1.5s”
• “API dependency failure > 10%”

This helps you stay ahead of issues.

🔗 Related Services We Offer

At QLLM Soft, we help startups and enterprises build, monitor, and scale production-ready systems. Explore our services:

• 👉 ASP.NET Core Development Services: High-performance apps tailored for growth
• 👉 Custom Software & API Development: Scalable APIs, backends, and cloud-ready platforms
• 👉 Cloud-Based Solutions: Migrate and optimize with Azure, AWS, and DevOps best practices
• 👉 Hire .NET Core Developers: Dedicated, affordable resources for your next project

🧠 Final Thoughts

In a DevOps world, you can’t fix what you can’t see. Application Insights brings real-time intelligence into your .NET Core apps — from code to cloud.

It’s fast to integrate, scalable with your growth, and a must-have for anyone serious about performance monitoring, error tracking, and data-driven improvement.

✅ Don’t fly blind. Monitor smarter. Ship confidently.
Need help integrating monitoring or scaling your .NET app? Talk to our experts →

📞 Contact Us Today

Website: https://qllmsoft.com
Email: info@qllmsoft.com
Phone/WhatsApp: +92 334 8229288
Location: Lalamusa, Pakistan
LinkedIn: QLLM Soft