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Infrastructure & Security Specialist specializing in Linux, VMware, Hyper-V, Windows Server, Oracle databases, infrastructure troubleshooting, security incident response, virtualization, and production systems support. I help businesses investigate security incidents, recover compromised Linux and WordPress environments, harden infrastructure, stabilize production systems, and resolve complex hosting, virtualization, and server issues. My experience includes: ✔ Security incident response & malware remediation ✔ WordPress malware removal & website recovery ✔ Server hardening & security auditing ✔ SSH, access control & authentication hardening ✔ VMware & Hyper-V virtualization ✔ Windows Server administration ✔ Linux systems administration ✔ Oracle Database administration & troubleshooting ✔ Infrastructure troubleshooting & performance analysis ✔ RAID, storage & recovery diagnostics ✔ VPS, dedicated server & hosting environments ✔ Backup & disaster recovery support ✔ PowerShell & Bash automation ✔ Email, DNS & server migrations ✔ Monitoring, stability & capacity planning Recent projects include security incident response and malware remediation across 155+ WordPress websites, Hyper-V VM scaling and performance stabilization, RAID recovery diagnostics on HPE servers, Linux/WHMCS migrations, Oracle environment troubleshooting, mail infrastructure troubleshooting, and production environment recovery. I focus on identifying root causes quickly, minimizing downtime, and delivering practical, production-ready solutions for critical systems and business infrastructure.

I’m a Senior System and Network Engineer with over 18 years of hands-on experience in IT infrastructure, cybersecurity, and cloud environments. As the founder of AOVD Systems, I help businesses and professionals around the world design, secure, and optimize their digital environments — from local servers to global cloud platforms. ⸻ 🔧 What I Do I deliver end-to-end IT solutions that are secure, scalable, and cost-efficient. My core areas of expertise include: • 🖥️ System Administration & Virtualization – Microsoft Server, VMware, Hyper-V, ESXi • ☁️ Cloud & Microsoft 365 Migration – Azure AD, Exchange Online, Intune • 🔐 VPN Configuration & Network Security – IPSec, SSL VPN, SAML, Multi-factor Authentication • 🧱 Firewall & Endpoint Protection – Fortigate, SonicWall, Cisco, Huntress, FieldEffect, Defender for Business • 💾 Backup & Disaster Recovery – Veeam, Nable, Acronis, Anxient • 📈 Network Performance & Monitoring – PRTG, Nagios, ManageEngine, NetFlow Analyzer • 🔄 Managed IT Services & Remote Support – 24/7 monitoring, patch management, SLA-based response ⸻ 🌍 Who I Work With I’ve supported clients across Europe and the U.S., including: • Government and public institutions • Small and medium businesses seeking reliable IT outsourcing • Professional poker players and private clients requiring secure, anonymous, and latency-optimized VPN setups • Teams transitioning from local servers to the cloud or hybrid infrastructure I combine enterprise-level knowledge with a hands-on, personal approach — ensuring speed, security, and discretion at every step. ⸻ 🎯 Why Clients Choose Me • Proven track record of resolving complex infrastructure issues under pressure • Certified expertise across multiple vendor ecosystems (Microsoft, Cisco, VMware, Veeam) • Transparent communication and detailed technical reporting • Tailored solutions — I don’t copy-paste templates, I solve your specific problem “Vladimir fixed in one hour what others couldn’t in three days.” “Professional, responsive, and precise. My systems are finally stable.” ⸻ 🎓 Certifications & Training • Microsoft Certified Solutions Expert (MCSE) – Server Infrastructure • Cisco Certified Network Professional (CCNP) – Routing & Switching • VMware Certified Professional (VCP) – Data Center Virtualization • Veeam Certified Engineer (VMCE) – Backup & Replication • Microsoft 365 & Azure Administrator Associate • Nagios & PRTG Advanced Monitoring Implementation • ManageEngine Suite Training – Endpoint Central & NetFlow Continuous learning is part of my work ethic — I stay updated with the latest in cybersecurity, automation, and cloud technologies to deliver cutting-edge solutions to every client. ⸻ 🚀 Let’s Work Together Whether you need a VPN configuration, network performance audit, or complete IT infrastructure management, I’ll help you build systems that are secure, stable, and future-ready. 📩 Let’s connect — tell me about your IT challenge, and I’ll design a fast, professional, and cost-effective solution.

🔬 Reverse Engineering & Security Analysis Binary analysis for security vulnerabilities, legacy system documentation, and interoperability Software activation integrity assessment to help vendors protect their IP Firmware unpacking, bootloader analysis, and embedded system forensics APK decompilation for security auditing and compliance 🛡️ Anti-Cheat Consulting & Game Integrity Reverse engineering of cheating tools to help game studios improve detection Design and audit of kernel-level anti-cheat systems (Windows, Linux) Memory integrity verification, handle stripping, and hypervisor-assisted detection Threat intelligence on cheat marketplaces and subscription models to strengthen product defense ☣️ Malware, Rootkit & Threat Analysis Full dissection of ransomware, backdoors, infostealers, and banking trojans Kernel-mode rootkit and bootkit forensics (DKOM, SSDT hooks, IRP filtering) Threat intelligence reporting with custom Yara rule creation Incident response support: rootkit and ransomware removal from servers and workstations 🔐 VPN & Network Security VPN setup, troubleshooting, and hardening (WireGuard, OpenVPN, IPsec) Traffic analysis, firewall configuration, and network segmentation Deep packet inspection (DPI) and protocol analysis for anomaly detection Secure infrastructure design for high-risk environments (journalists, activists, enterprises)

✅ Professional Penetration Tester ✅ 3500+ Hours ✅ Top Rated Plus Freelancer Security Researcher and Penetration Tester recognized by the U.S. Department of Defense, AT&T, Sony, and Semrush for the responsible disclosure of 40+ vulnerabilities via HackerOne. Since 2022, an active member of the Synack Red Team - an elite tier of offensive security specialists vetted through rigorous technical and background screening. Every engagement concludes with a comprehensive technical report built to satisfy the specific penetration testing controls required for HIPAA, ISO 27001, SOC2, and PCI-DSS. I provide a high-level executive summary for stakeholders alongside deep-dive technical findings, fully reproducible Proofs-of-Concept (PoCs), and prioritized remediation steps to ensure your team can effectively close every gap before your audit. Specializing in black and gray box testing of live web applications, cloud environments, and networks, covering all common attack vectors, business logic flaws, and discovering previously undisclosed vulnerabilities (0days) to prevent high-impact data breaches. Service Description: 1) Web Application Penetration Testing (OWASP Top 10, PTES, ASVS, Business Logic Testing) 2) Mobile Application Penetration Testing (OWASP Top 10, MASVS, MASTG, PTES) 3) Network Penetration Testing (Active Directory, Entra ID, Internal & External Network) 4) API Security Testing - REST, GraphQL, SOAP, gRPC, Webhooks (OWASP API Top 10) 5) Cloud Security Testing - AWS/Azure/GCP/OCI/Alibaba/IBM/DigitalOcean/SaaS/IaaS/PaaS 6) Cloud-Native & Container Security (Kubernetes, Docker, OpenShift, EKS/AKS/GKE) 7) LLM Security Testing (OWASP LLM Top 10, Prompt Injection, Data Poisoning) Tools used in engagements: BurpSuite Professional | Custom Python scripts | BloodHound | Impacket Framework | Responder | Metasploit | Mimikatz | Nuclei | Nmap | FRIDA | Android Studio | Pacu | Prowler | Postman Identify and secure your attack surface before threat actors do ! Message me to discuss your project requirements.

Network & IT Infrastructure Expert | Mikrotik | VPN | Linux | Cloud With 25 years of experience in IT infrastructure and network engineering, I specialize in designing, securing, and optimizing network systems for businesses of all sizes. Whether you need a reliable VPN solution, a secure network setup, or an optimized server infrastructure, I can help you achieve your goals efficiently. What I Offer: Mikrotik & Network Configuration – Routing, Firewall, VLANs, QoS, Wireless VPN & Secure Networking – WireGuard, OpenVPN, IPsec, GRE tunnels Linux System Administration – Ubuntu, CentOS, Debian, server automation Cloud & Backup Solutions – Veeam, Rsync, ZFS, Proxmox, Disaster Recovery Server & API Hosting – OpenStreetMap servers, self-hosted solutions Troubleshooting & Performance Optimization – Network monitoring, security hardening I have worked with businesses, startups, and enterprise clients to ensure their IT infrastructure is secure, scalable, and high-performing. My approach is straightforward – I analyze, optimize, and deliver solutions that just work. Let’s connect and discuss how I can help with your project!

👑 Expert Vetted - Top 1% of all Upwork Freelancers - Top Rated Network and Cloud Engineer. - 300+ projects and 7000+ Upwork hours up to date. - 600k+ earned on Upwork. Networking vendors I have worked with: * Cisco, Mikrotik, Fortigate, Ubiquiti, Vyatta, VyOS, pfSense, Sonicwall, Sophos XG, Watchguard, Brocade, Ruckus, HP, Huawei, HPE, Aruba, Arista, etc. Cloud Skills: Terraform (AWS, Azure, GCP) AWS - VPC, EC2, RAM, R53, LB, S3, IAM/SSO, various NGFWs, Terraform. Azure - AD, AADDS, S2S VPNs, VMs, LB, NGFWs, Azure Hub-Spoke, Terraform. GCP - Cloud Compute, Security, NGFWs, Terraform. Digital Ocean Vultr ...