Percio Castelo

The story

I spent the last ten years inside production Linux servers: Tier 2/3 advanced technical support at HostGator Latin America and technical consulting, managing hosting environments with cPanel/WHM, DirectAdmin, and HestiaCP, handling Exim and Postfix mail queues, applying server hardening, and recovering offline services under pressure.

This blog originated from the hands-on habit of documenting every technical problem and its definitive fix: what the error log indicated, the exact root cause, and the configuration needed to harden the server and prevent recurrence. Practical diagnostics and procedures with real production commands.

Today, beyond routine infrastructure, I bring this experience to my continuous studies and practice in Docker, CI/CD automation, and security within the NEXUS ecosystem. Transitioning to DevOps and DevSecOps is the natural result of years in real operations combined with a focus on stability and automation.

The method behind every article

• Careful reproduction and analysis of issues based on real server incidents and production scenarios.
• Authentic terminal commands, logs, and outputs — proven solutions tested in production.
• Root cause explained at the exact technical layer (service, configuration, permissions, DNS, or network).
• Hardening and operational prevention to guarantee continuous stability.

Where to navigate

• Blog — practical tutorials, diagnostics, and troubleshooting guides
• Projects — tools, automations, and the NEXUS ecosystem
• Services — Linux infrastructure consulting, hardening, and technical support
• Certificates — continuous education in infrastructure and security
• Rankings — technical benchmarks of hosting providers and control panels