open-source-tools.md

There are numerous open-source tools available for troubleshooting operating systems across various aspects like running processes, open ports, network connections, hardware usage (CPU, memory, disk, network), and logs. Below is a categorized list of popular open-source tools that can help with these tasks, primarily focusing on Linux/Unix systems, but some are cross-platform and work on Windows or macOS as well.

1. Running Processes

• top: Real-time system-monitoring tool for Unix systems, displays CPU and memory usage by processes.
  • Alternative: htop (enhanced, user-friendly version with a colorful interface and process management features).
• ps: Displays a snapshot of current processes, highly customizable for filtering and formatting output.
• pidstat (part of sysstat): Monitors individual process statistics like CPU, memory, and I/O usage over time.
• Glances: Cross-platform system-monitoring tool that provides a comprehensive view of processes, CPU, memory, and more in a single interface.

2. Open Ports

• netstat (part of net-tools): Displays open ports, active connections, and routing tables (though somewhat deprecated in favor of newer tools).
• ss: Modern replacement for netstat, faster and provides detailed socket statistics, including open ports and listening services.
• nmap: Network exploration tool and port scanner, useful for discovering open ports and services on local or remote systems.
• lsof: Lists open files, including network sockets, to identify which processes are using specific ports.

3. Open Network Connections

• netstat and ss: As mentioned, both show active network connections, including TCP/UDP states and associated processes.
• iftop: Displays real-time network bandwidth usage by connection, showing active network connections and their data rates.
• nload: Monitors network traffic and bandwidth usage, useful for identifying high-traffic connections.
• Wireshark: Open-source packet analyzer for detailed inspection of network connections and traffic (cross-platform).
• tcpdump: Command-line packet analyzer for capturing and analyzing network traffic, useful for troubleshooting connection issues.

4. Hardware Usage (CPU, Memory, Disk, Network)

• CPU Usage:
  • top/htop: Real-time CPU usage per process and system-wide.
  • mpstat (sysstat): Detailed CPU usage statistics, including per-core metrics.
  • vmstat: Reports virtual memory and CPU usage statistics.
• Memory Usage:
  • free: Displays memory usage (total, used, free, and cached).
  • vmstat: Provides memory statistics alongside CPU.
  • htop/Glances: Visualizes memory usage by processes.
• Disk Usage:
  • df: Reports disk space usage for mounted filesystems.
  • du: Estimates file and directory space usage.
  • iotop: Monitors disk I/O usage by processes in real-time.
  • iostat (sysstat): Provides disk I/O and CPU statistics.
• Network Usage:
  • iftop/nload: Real-time network bandwidth monitoring.
  • vnstat: Lightweight network traffic monitor with historical data tracking.
  • bmon: Bandwidth monitor for network interfaces.

5. Logs

• journalctl (systemd): Queries and displays logs from the systemd journal, widely used in modern Linux distributions.
• tail: Monitors log files in real-time (e.g., tail -f /var/log/syslog).
• less/more: Paginates and searches through large log files.
• grep: Filters log files for specific patterns or errors (e.g., grep "error" /var/log/messages).
• logrotate: Manages and rotates log files to prevent disk space issues (not for analysis but for log maintenance).
• rsyslog/syslog-ng: Centralized log management systems for collecting, filtering, and storing logs.
• ELK Stack (Elasticsearch, Logstash, Kibana): Open-source suite for centralized log aggregation, analysis, and visualization (more complex setup).

6. Comprehensive Monitoring Tools

• Nagios Core: Open-source monitoring system for tracking system resources, network services, and logs (requires setup).
• Zabbix: Enterprise-grade monitoring tool for hardware, network, and application performance with log monitoring capabilities.
• Prometheus: Time-series-based monitoring tool with powerful querying, often paired with Grafana for visualizing CPU, memory, disk, and network metrics.
• Cockpit: Web-based interface for Linux server management, including process, network, storage, and log monitoring.

7. Cross-Platform Tools

• Wireshark: Packet analysis for network troubleshooting (Linux, Windows, macOS).
• Glances: System monitoring with a web interface (Linux, Windows, macOS).
• Sysdig: System-level monitoring and troubleshooting with detailed insights into processes, network, and disk (Linux, with some Windows support).
• Process Explorer (Windows-specific, open-source alternative to Task Manager): Detailed process and resource usage for Windows systems.

Installation Notes

• Most of these tools are available in default package repositories for Linux distributions (e.g., apt install htop on Debian/Ubuntu, yum install htop on CentOS, or pacman -S htop on Arch).
• For cross-platform tools like Wireshark or Glances, check their official websites or package managers (e.g., Homebrew on macOS, Chocolatey on Windows).
• Some tools like ELK Stack, Nagios, or Zabbix require more complex setup but offer powerful features for large-scale systems.

Recommendations

• For quick troubleshooting: Use htop, ss, iotop, and journalctl for a lightweight, real-time overview.
• For network issues: Combine nmap, Wireshark, and tcpdump for detailed analysis.
• For comprehensive monitoring: Set up Prometheus with Grafana or Zabbix for long-term insights.
• For logs: Start with journalctl or grep for quick checks, and scale to ELK Stack for centralized log management.

system-monitoring.md

There are open-source tools that combine multiple troubleshooting capabilities (e.g., monitoring processes, ports, network connections, hardware usage, and logs) into a single solution, allowing on-demand execution to diagnose and report system issues. These tools typically provide a unified interface or scriptable workflows to identify problems and generate reports, making them ideal for troubleshooting. Below, I’ve listed some of the most relevant open-source tools that meet your criteria, focusing on their ability to run on demand, troubleshoot across multiple system aspects, and report issues.

1. Sysdig

• Description: Sysdig is an open-source, system-level monitoring and troubleshooting tool that provides deep visibility into processes, network connections, file I/O, CPU, memory, and logs. It’s designed for on-demand diagnostics and can generate detailed reports.
• Features:
  • Monitors running processes with CPU/memory usage and parent-child relationships.
  • Captures network connections and open ports (similar to netstat or ss).
  • Tracks disk I/O and file access.
  • Analyzes system calls and logs for debugging.
  • Generates JSON or human-readable reports of system activity.
• On-Demand Use: Run sysdig with filters (e.g., sysdig -c topprocs_cpu for top CPU processes) to troubleshoot specific issues and output results to a file for reporting.
• Reporting: Supports exporting traces or summaries to files, which can be parsed or shared.
• Platform: Primarily Linux, with limited Windows support.
• Installation: Available via package managers (e.g., apt install sysdig on Ubuntu) or Docker.
• Example: sysdig -p "proc.name=%proc.name cpu=%cpu" > report.txt to log process CPU usage.
• Why It Fits: Combines process, network, disk, and log analysis in one tool with flexible, on-demand execution and reporting.

2. Glances

• Description: Glances is a cross-platform, open-source system monitoring tool that provides a comprehensive view of system resources (CPU, memory, disk, network, processes, and logs) in a single interface. It’s lightweight and can be run on demand.
• Features:
  • Displays top processes by CPU/memory usage.
  • Shows network usage and open connections.
  • Monitors disk I/O and filesystem usage.
  • Alerts on high resource usage or potential issues (e.g., memory saturation).
  • Can export data to CSV, JSON, or integrate with external tools like Grafana.
• On-Demand Use: Run glances in terminal or web mode (glances -w) for real-time diagnostics. Use --export for reports.
• Reporting: Exports metrics to files or databases, with customizable thresholds for issue detection.
• Platform: Linux, Windows, macOS.
• Installation: Install via pip (pip install glances) or package managers (apt install glances).
• Example: glances --export-csv /tmp/glances-report.csv to generate a report of system metrics.
• Why It Fits: Provides a unified view of system health, detects anomalies, and supports on-demand reporting.

3. Cockpit

• Description: Cockpit is an open-source, web-based server management tool for Linux that allows on-demand monitoring and troubleshooting of processes, network, storage, and logs. It’s user-friendly for both admins and developers.
• Features:
  • Monitors running processes and resource usage (CPU, memory).
  • Displays disk usage and I/O activity.
  • Shows network interfaces and traffic.
  • Views and searches system logs (via journalctl integration).
  • Alerts on critical issues like high CPU or disk space.
• On-Demand Use: Access Cockpit via a browser (http://localhost:9090) to check system status and diagnose issues in real time.
• Reporting: Logs and metrics can be exported manually, or you can integrate with external tools for automated reporting.
• Platform: Linux (primarily RHEL, Fedora, Ubuntu, Debian).
• Installation: apt install cockpit on Debian/Ubuntu or dnf install cockpit on Fedora.
• Example: Use the web interface to view logs and save them as text files for reporting.
• Why It Fits: Combines multiple monitoring aspects in a web interface, ideal for quick, on-demand troubleshooting.

4. Prometheus with Node Exporter

• Description: Prometheus is an open-source monitoring system with a time-series database, and its Node Exporter collects system metrics (CPU, memory, disk, network, processes). While typically used for continuous monitoring, it can be run on demand for troubleshooting.
• Features:
  • Collects detailed metrics on CPU, memory, disk, and network usage.
  • Monitors open file descriptors and process counts.
  • Tracks network interface statistics.
  • Integrates with Grafana for visualizing issues.
  • Alerts on thresholds (e.g., high CPU usage).
• On-Demand Use: Start Node Exporter (./node_exporter) and query Prometheus via its web UI or API to analyze metrics and identify issues.
• Reporting: Export metrics as JSON or use Grafana dashboards for visual reports.
• Platform: Linux, with partial Windows/macOS support via exporters.
• Installation: Download binaries from the Prometheus website or use package managers.
• Example: curl http://localhost:9100/metrics > metrics.txt to save system metrics for analysis.
• Why It Fits: Comprehensive metrics collection with flexible querying for on-demand diagnostics, though setup is slightly more involved.

5. Monit

• Description: Monit is an open-source utility for monitoring and managing system processes, files, directories, and devices. It can be used on demand to check system health and report issues.
• Features:
  • Monitors processes for CPU/memory usage.
  • Checks network ports and connections.
  • Tracks disk usage and filesystem health.
  • Analyzes logs for errors.
  • Sends alerts via email or executes scripts on issues.
• On-Demand Use: Run monit status to get a snapshot of system health or use its web interface for interactive troubleshooting.
• Reporting: Generates status reports and logs alerts to files or email.
• Platform: Linux, Unix, with some Windows support.
• Installation: apt install monit on Debian/Ubuntu or compile from source.
• Example: monit report > system-report.txt to save a system status report.
• Why It Fits: Lightweight and focused on actionable troubleshooting with reporting capabilities.

6. Custom Scripts with Standard Tools

• Description: You can combine standard open-source tools (e.g., htop, ss, iostat, journalctl) into custom Bash or Python scripts to run on demand, troubleshoot issues, and generate reports. This approach is highly flexible.
• Features:
  • Use ps or top for process monitoring.
  • Use ss or netstat for ports and connections.
  • Use iostat or df for disk/CPU metrics.
  • Use journalctl or grep for log analysis.
  • Aggregate outputs into a single report file.
• On-Demand Use: Execute the script (e.g., ./troubleshoot.sh) to collect and analyze data.
• Reporting: Scripts can output to text, CSV, or JSON files for reporting.
• Platform: Linux (cross-platform with modifications).
• Example Script:

  #!/bin/bash
  echo "System Troubleshooting Report - $(date)" > report.txt
  echo "=== Processes ===" >> report.txt
  ps aux --sort=-%cpu | head -n 10 >> report.txt
  echo "=== Open Ports ===" >> report.txt
  ss -tuln >> report.txt
  echo "=== Disk Usage ===" >> report.txt
  df -h >> report.txt
  echo "=== Recent Logs ===" >> report.txt
  journalctl -p 3 -n 50 >> report.txt
  echo "Report generated: report.txt"

• Why It Fits: Fully customizable to your needs, leveraging existing tools for a tailored troubleshooting solution.

Recommendations

• For Simplicity: Use Glances or Cockpit for a quick, unified interface that covers most troubleshooting needs with minimal setup.
• For Deep Diagnostics: Use Sysdig for detailed system-level insights, especially for complex issues involving processes, network, or I/O.
• For Flexibility: Write a custom script combining tools like ss, iostat, and journalctl for targeted, on-demand reports.
• For Advanced Reporting: Set up Prometheus with Node Exporter and Grafana for detailed metrics and visual reports, though it requires more configuration.

Notes

• Installation: Most tools are available in Linux package repositories (e.g., apt, yum, pacman) or via source compilation. For cross-platform tools like Glances, use pip or platform-specific installers.
• Reporting: Ensure output formats (e.g., CSV, JSON, text) match your needs for sharing or further analysis.
• Platform: Most tools are Linux-focused, but Glances and custom scripts can be adapted for Windows/macOS with tools like PowerShell or Process Explorer.
• Automation: For recurring issues, tools like Monit or Prometheus can be configured to run periodically and alert on problems.