Microservices and distributed systems became the norm over the last couple of years. With all the benefits of having small, decoupled units of processing messages and requests, comes the pain. The pain of losing control. The pain of not knowing what exactly happened when users start to complain that some part of a large system misbehaves.

We learned about monitoring, metrics and traces - those pillars of observability. We use a bunch of tools to collect and categorise the information, but then we start drowning in the sea of logs, graphs and dashboards.

OpenTelemetry aims to address all aspects of collecting the insights of distributed systems using one API and one protocol. With the release of .NET 6, we got a new way to collect metrics, provided by the standard package. Let's look together how a distributed system built with .NET 5 and 6 can be instrumented to use OpenTelemetry and how can we use all the information it delivers to diagnose complex issues and get alerted properly when things don't go well.

Proper instrumentation and alerting will, for sure, save your day more than once. It will also save your nights and weekends too.