Best Linux Free Open-Source Monitoring Software

Agent for collecting, processing, aggregating, and writing metrics, logs, and other arbitrary data

Real-time system monitoring and performance troubleshooting

Monitoring system and time series database

Fast, header-only C++ logging library for high-performance applications

Advanced Node.js process manager for production environments

Simple and easy-to-use Python logging library

Cross‑platform real‑time system monitoring for admins and DevOps