Microsoft Sentinel Implementation Lessons: What You Should Know Before You Start

Microsoft Sentinel is one of the most powerful cloud-native SIEM and SOAR platforms available today. But implementing it? That’s a different story.

Beneath the polished dashboards and seamless integration promises lies a complex cluster of Microsoft technologies stitched together. If you’re expecting a plug-and-play experience, think again. Sentinel demands expertise, time, and a lot of operational patience—especially in the early stages of deployment.

Here are some of the key lessons we learned during our latest Sentinel implementation project.

It’s a Collection of Services, Not a Single Tool

Microsoft Sentinel is marketed as a unified security solution. And while the front-end experience is cohesive, the backend is anything but simple.

Under the hood, Sentinel relies on a combination of Azure Monitor, Log Analytics, Logic Apps, Azure Functions, and more. These are powerful tools in their own right, but they require deep knowledge to manage effectively. Operational teams must be comfortable navigating these layers—not just configuring alerts and dashboards, but also managing ingestion costs, query performance, and runbook automation.

This adds a significant workload to already stretched security and infrastructure teams.

Data Connectors: A Mixed Bag

Data ingestion is where most of the early project time will be spent—and often re-spent.

You’re typically presented with a choice between deprecated connectors (still widely used, oddly enough) and preview connectors (not fully supported). This creates uncertainty around reliability and long-term viability. Even connecting core Microsoft services can be trickier than expected.

Expect to spend more time than planned setting up and testing connectors, particularly for on-premises systems. Agents, firewalls, outdated documentation—it all adds up quickly.

On-Premises Integration is High-Effort

If your environment includes on-premises infrastructure (and most do), be prepared for a significant lift.

Connecting legacy systems, especially those not running the latest OS or patch levels, often requires workarounds. We encountered missing documentation, inconsistent error messages, and complex permission requirements just to get basic logs into Sentinel.

This is a key planning point: don’t underestimate the resource cost of on-premises integration. Factor in time for testing, troubleshooting, and collaboration between infrastructure, security, and application teams.

It Sometimes Feels Like You’re the First User

Microsoft Sentinel is a relatively new product in the SIEM space, and its maturity level reflects that.

We encountered spelling mistakes in core log event mappings—yes, even for Microsoft’s own technologies like Exchange. Some event IDs didn’t match official documentation. Other times, critical fields were simply missing or mislabeled.

These issues erode trust in the platform and increase the time required to tune analytics and create custom rules. Be prepared to validate everything, especially early on.

Unified Visibility is a Game Changer

Despite the rough edges, the value Sentinel offers once it’s up and running is hard to ignore.

Integration with other Microsoft security tools—like Defender for Endpoint, Microsoft Entra, Microsoft Secure Score, and Vulnerability Management—provides a true single pane of glass. Correlation across these services enables deeper insights with fewer manual investigations.

And perhaps the biggest operational win? Free data ingestion from Microsoft’s cloud services. Logs from Defender, Microsoft 365, Azure AD, and other Microsoft sources don’t count against your data cap, which can significantly reduce operating costs.

Final Thoughts: It’s 80% Done… But Worth It

Like many Microsoft cloud products, Sentinel has the familiar “80% complete” feel. The foundation is strong. The vision is compelling. But you’ll run into quirks, unfinished features, and documentation gaps that make it clear the product is still maturing.

Still, the long-term value is there. If you’re committed to the Microsoft ecosystem and ready to invest the effort upfront, Sentinel can provide scalable, integrated, and intelligent security operations.

Just go into it with your eyes open—and your sleeves rolled up.

Element Digital offers IT Consulting Services in Hobart, dedicated to providing expert guidance and strategic planning for all your IT needs. Our Hobart-based IT Professional Services are tailored to meet the diverse requirements of businesses in Tasmania. For more insights and updates, follow us on LinkedIn and stay connected with #ElementDigital.