Networking: Firewall permissions, DNS, TCP/IP, HTTP/HTTPS, SSL/TLS, server/VM management
Virtualization, cloud computing, and security: Amazon Web Services, Microsoft Azure, Google Cloud
Containerization: Kubernetes, Docker, Amazon ECS, Azure AKS
API: REST, JSON, web tokens, testing tools (like Postman)
Frontend web: HTML5, CSS, JavaScript
Backend: Databases (MySQL), PHP, Python, CLI, system health monitoring tools
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