Jaeger is a modern, secured, distributed, highly-scalable, SPoF avoided tracing system ( open sourced ). It can be used for monitoring microservice-based architectures with a Javascript / React Web UI and Cloud deployed collection of Docker images, operating as the system-backend.
The WHY part :
The majority of operational problems that arise when moving to a distributed architecture are ultimately grounded in two areas:
networking and
observability.
It is simply an orders of magnitude larger problem to network and debug a set of intertwined distributed services versus a single monolithic application.
Git: https://github.com/jaegertracing/jaeger
Doc: https://jaegertracing.io/docs/