David Rainear Jr

Systems Administrator & IT Infrastructure Specialist

Over 4 years of enterprise IT experience specializing in Windows/Linux system management, Active Directory, SCCM/Intune deployment, PowerShell automation, and endpoint security. Cisco Certified with a proven track record of optimizing system performance and operational efficiency.

David Rainear Jr
4+
Years Experience
200+
Users Supported
Enterprise
IT Environments
Cisco
Certified

Professional Experience

IT Support Specialist – Tier 3
Resorts Casino – Atlantic City, NJ
March 2024 to Present
  • Administered Active Directory OUs, group policies, and account lockouts for 200+ users in a highly regulated casino environment
  • Configured Azure AD Conditional Access and MFA policies; resolved complex identity and authentication failures
  • Managed enterprise patch deployment and OS updates via SCCM and Intune across all departments
  • Diagnosed and resolved Omnissa Horizon (formerly VMware Horizon) VDI issues including profile corruption, GPO conflicts, and connection failures
  • Developed PowerShell and Batch scripts to automate file cleanup, print spooler resets, and remote reboots
  • Built and maintained SCCM/Intune OS images and software deployment task sequences; remediated deployment failures
  • Served as sole on-site technician during evening shifts, owning outage response and coordinating with remote teams
  • Authored internal documentation and technical guides to train junior staff and standardize troubleshooting steps
  • Performed Ethernet cable terminations, patch-panel punchdowns, and static IP configuration on Windows endpoints
  • Conducted daily tape backups and supported business continuity for IBM iSeries Power10 systems
IT Technician – Tier 2 Support
Universal Mold & Tool, INC. – Vineland, NJ
January 2021 to March 2024
  • Delivered full-scope IT support for manufacturing operations, including provisioning, networking, and hardware upkeep
  • Managed imaging, OS/application installations, and patching across desktops, printers, and mobile devices
  • Created and maintained user accounts and group permissions within Active Directory
  • Provided comprehensive end-user support and resolved technical issues across multiple device types

Technical Skills

🖥️ System Administration

  • Windows Server Administration
  • Linux System Management
  • Active Directory (OUs, GPOs)
  • Azure AD & Conditional Access
  • SCCM / Intune (MDM)
  • Omnissa Horizon VDI

🔒 Security & Access Control

  • MFA Implementation
  • System Hardening
  • SSH Key Authentication
  • Fail2ban Configuration
  • Firewall Management
  • Log Analysis & Monitoring

⚙️ Automation & Scripting

  • PowerShell Scripting
  • Batch Scripting
  • Crontab / Task Scheduling
  • Deployment Automation
  • System Maintenance Scripts

🌐 Networking & Infrastructure

Personal Projects

Self-Hosted Security Stack

Deployed Pi-hole (DNS sinkhole), Unbound (DNS resolver), and WireGuard (VPN) on Raspberry Pi to provide encrypted remote access, DNS filtering, and comprehensive ad/tracker blocking for home network.

Pi-hole Unbound WireGuard Raspberry Pi

Linux System Hardening

Implemented SSH key-based authentication to replace password logins, configured Fail2ban to detect and block brute-force attempts, and secured remote access with custom firewall rules.

SSH Fail2ban iptables Linux Security

Dynamic DNS & Remote Access

Configured dynamic DNS for reliable external connectivity, enabling secure access to home services without relying on static IP assignments. Automated updates and monitoring.

DDNS Automation Debian

Cybersecurity Training

Active training on TryHackMe platform, focusing on Linux administration, networking fundamentals, threat detection, log analysis, and SOC workflows to enhance security expertise.

TryHackMe Threat Detection SOC

Let's Connect

Looking for an experienced systems administrator who can optimize your IT infrastructure, automate processes, and enhance security? I'd love to discuss how I can help your organization.

📧 Email Me 📞 Call Me

📍 Based in Estell Manor, NJ. Targeting roles in Charlotte NC and Charleston SC.