Systems Administrator; Unix​/Linux

About NDi

Network Designs, Inc. (NDi) is a leading Federal contractor that specializes in designing, developing, and delivering information technology and network solutions for government customers. Founded in 1985, NDi's firmly defined core values have driven all aspects of the business, which have been paramount to our company's success and the establishment of an enjoyable workplace atmosphere. At NDi, we believe that our people are the cornerstone of our success, and we value collaboration, career growth, and winning ideas.

NDi is seeking a skilled Systems Administrator (Unix/Linux) to provide enterprise-level administration and support for a large, mission‑critical federal IT program.

The Systems Administrator will manage and maintain Unix and Linux systems across multiple environments, ensuring reliable, secure, and efficient operations. This role involves system installation, configuration, performance tuning, troubleshooting, and applying cybersecurity controls consistent with DoD and federal security standards.

• U.S Citizenship required.
• Active Top Secret Clearance required.
• This position requires 5 days onsite in Dahlgren, VA. Please note that up to 40% remote work may become available but this determination will be made at a later stage.

• Six (6) of professional experience in Unix and/or Linux system administration of networks and software systems.
• System backup and recovery, basic software management, security management, and library management.
• Installation and configuration of hardware, COTS software, and operating systems across multiple environments.
• Skilled in sizing, performance tuning, troubleshooting, and resource allocation for hardware, software, and network components.
• Qualified experience with network protocols including TCP/IP and major network security tools such as firewalls; knowledge of computing and networking vulnerabilities, attack methods, and detection techniques.
• Certifications (DoD 8570/8140 IAT Level III), minimum of one: CASP+ CE, CCNP Security, CISA, CISSP (Associate or Full), GCED, GCIH, CySA+ CE, CCSP, Pen Test+ CE, or GSE.
• If you do not currently hold any of the above certifications, you must be willing to obtain one by March 1, 2026.
• Proven ability to manage and secure complex Unix/Linux environments in compliance with DoD STIG and RMF requirements.
• Advanced system administration and scripting in Unix/Linux environments.
• Knowledge of DoD cybersecurity policies, RMF, and STIG implementation.
• Strong diagnostic and problem‑resolution skills.
• Familiarity with enterprise monitoring and configuration‑management tools.
• Excellent communication and documentation abilities.

• Master's level degree in Electrical/Electronic/Computer Engineering, Computer Science, or Information Systems.

• Install, configure, and maintain Unix/Linux servers, ensuring uptime and performance.
• Perform system backups, restores, and patch management.
• Implement and monitor security measures to protect systems and data.

• Manage and troubleshoot TCP/IP network configurations.
• Configure and maintain firewalls and other network security tools.
• Identify vulnerabilities and implement mitigation or remediation strategies.

• Analyze system performance metrics and conduct capacity planning.
• Provide Tier III support for complex technical issues.
• Collaborate with engineering, cybersecurity, and operations teams to ensure secure, optimized system performance.

At NDi, we value our team and are committed to retaining top talent by offering competitive benefits and compensation packages. Our employee benefits package includes comprehensive health, dental, vision, pet, and legal insurance. Our corporate benefits include 401(k) retirement matching, paid leave, paid holidays, and health and wellness programs. In addition, we provide employer‑paid life and disability insurance, professional development, education benefits, and much more to ensure our team has the resources they need…