Serhii Kravchenko
Private message
Offer work
Kyiv,
Ukraine
available for hire
Rating
Language proficiency level
Українська: fluent
Русский: fluent
English: intermediate
Deutsch: elementary
CV
Senior Infrastructure Engineer / System Administrator (10+ Years of Experience)
I design, deploy, and maintain server environments and network infrastructure. I take full ownership of the technical stack: from basic VPS configuration to building secure VPN tunnels and automating daily operations. I work autonomously without the need for micromanagement.
Core Competencies:• OS & Servers: Linux (Debian, Ubuntu, CentOS), Windows Server. • Virtualization: Proxmox VE, KVM, Docker. • Networking & Security: Routing (BGP, OSPF), VPN (WireGuard, OpenVPN, IPsec), MikroTik, Firewalls (iptables), DDoS mitigation. • Automation: Python and Bash scripting (automated backups, web scrapers, Telegram monitoring bots). • Monitoring: Zabbix, Grafana.
How I Work:You outline the problem — I propose an optimal technical solution and deliver it turnkey. Always strictly adhere to deadlines. Available during EET business hours.
Open to one-time tasks, complex troubleshooting, and long-term part-time collaboration.
Skills and abilities
Programming
Services
Photo, Audio & Video
Administration
Writing
Portfolio
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Linux Server Security Audit: A Practical Toolkit for Sysadmins
Articles & Blog Posts
A practical guide to conducting a comprehensive security audit of Linux servers, aimed at system administrators. The article contains a list of critical checks to strengthen the infrastructure, including access rights control, network port auditing, firewall configuration, and analysis of vulnerabilities in system services. The main focus is on using open-source tools (Lynis, Lynis Enterprise, Lynis-audit, and standard Bash utilities) to automate routine checks and build a reliable security monitoring system.