Open source software is driving the advancement of DevOps by offering flexibility, speed, and cost-efficiency, prompting organizations to adopt open-source tools for monitoring and observability in IT environments. The text discusses various open-source monitoring tools like Grafana, Prometheus, OpenTelemetry, Graphite, InfluxDB, Fluentd, Jaeger, and the ELK Stack, each with its own strengths and challenges, particularly regarding scalability and ease of use. The article highlights the growing complexity of IT environments and the trade-offs involved in using open-source tools, such as the time and resources needed for deployment and maintenance. It also introduces Logz.io, a SaaS platform that unifies several open-source monitoring tools to simplify management and enhance observability. While open-source tools do not require direct financial investment, they can incur significant operational costs, especially when scaled for production use.