Network System Administrator

Amentum; Washington (District of Columbia); On-site; USD 120,000 - 150,000; Full time

Benefits offered by this job

Health, dental, and vision insurance

Paid time off

401(k) matching

Educational reimbursement

Parental leave

Employee stock purchase plan

Job summary

Amentum is seeking a Network Systems Administrator to support NASA Headquarters in a full-time on-site capacity in Washington, DC. You will manage enterprise network infrastructure, mixed-server environments, and secure mission-critical systems across Windows, Linux, and Proxmox virtualization.

The ideal candidate has strong network engineering and systems administration skills, plus experience in security compliance, documentation, and cross-functional team leadership for project execution.

Qualifications

• Active Top Secret clearance with SCI access; CI Polygraph required.
• DoD 8570.01-M IAT II certification (e.g., Security+ CE) before start.
• Associate degree or higher in CS/IT/Networking, or equivalent work exp.
• Expert knowledge of TCP/IP, DNS, VLANs, VPNs, and network devices.
• Proven Windows Server, AD, and Linux administration experience.
• Proxmox VE virtualization experience; VM orchestration and DR testing.

Responsibilities

• Administer and secure LAN/WAN environments, routers, switches, firewalls, VPNs, VLANs.
• Monitor performance, troubleshoot connectivity, apply configuration changes for high availability.
• Document network diagrams, baselines, and procedures.
• Manage Proxmox clusters, Windows/Linux OS deployments, backups, and DR validation.
• Harden and monitor systems per RMF and STIG policies; collaborate with ISSO/ISSM.

Skills

Network administration

Windows Server

Linux

Proxmox VE

Scripting

Active Directory

Tools

COTS/GOTS software

Firewall/VPN

RMF/STIG

Job description

Amentum is seeking a highly motivated and skilled Network Systems Administrator to support NASA Headquarters. In this full-time, on-site role, you will be responsible for managing and securing an enterprise network infrastructure and mixed-server environment. This role supports the full lifecycle of IT systems, ensuring the availability, performance, security, and compliance of mission‑critical infrastructure. The ideal candidate will possess a strong primary background in network administration and engineering, coupled with robust systems administration experience across Windows, Linux, and Proxmox virtualization platforms. The candidate should have experience leading cross‑functional teams from project conception through successful execution.

You will play a critical role in supporting diverse operations, managing COTS and GOTS hardware and software, and ensuring strict adherence to government cybersecurity policies.

Key Responsibilities

Network Administration & Engineering

• Administer and maintain complex LAN/WAN environments, including routers, switches, firewalls, VPNs, VLAN configurations, and network segmentation.
• Monitor network performance, troubleshoot connectivity issues, and implement configuration changes to ensure high availability and security.
• Maintain detailed documentation of network diagrams, configurations, system baselines, and operational procedures.

Infrastructure & Virtualization Management

• Administer, maintain, and optimize Proxmox VE virtualization clusters to ensure high availability and resource efficiency.
• Manage Windows Server environments, including Active Directory, Group Policy, DNS, patch management, antivirus updates, and system upgrades.
• Deploy, configure, and manage Windows and Linux operating systems within virtualized and physical environments.
• Perform regular backups and disaster recovery validation to ensure data integrity across all server and storage environments.

Security, Compliance & Access Control

• Configure, harden, and monitor network and system environments in accordance with government security standards (e.g., STIGs).
• Continuously monitor system logs, network traffic, and security alerts.
• Investigate, document, and report incidents, vulnerabilities, and threats.
• Collaborate with ISSO/ISSM and security staff to ensure all system changes comply with RMF (Risk Management Framework) and local security policies.

Desktop Support & IT Lifecycle Management

• Install, configure, and maintain Commercial Off-The-Shelf (COTS) and Government Off-The-Shelf (GOTS) software applications.
• Provide desktop support for Windows workstations, resolving complex user issues and deploying new hardware/software.
• Provide full lifecycle management of IT infrastructure, including procurement support, deployment, configuration management, and secure decommissioning of hardware and software assets.

Required Qualifications

• Must possess an active US Government Top Secret security clearance with the ability to obtain SCI and must consent to a CI Polygraph. Please note US Citizenship is required to maintain a Top Secret clearance.
• Must meet DoD 8570.01-M Information Assurance Technical (IAT) Level II certification requirements (e.g., CompTIA Security+ CE) prior to starting date.
• Associate degree or higher in Computer Science, Information Technology, Network Engineering, or a related field (or equivalent work experience) with at least 5 to 8 years of relevant IT experience.
• Networking: Expert knowledge of network protocols (TCP/IP, DNS, VLANs, VPNs), LAN/WAN management, routing, switching, and hands‑on experience with hardware firewalls and VPNs.
• Systems Administration: Proven experience with Windows Server, Active Directory, and Linux system administration.
• Virtualization: Hands‑on experience building and managing virtual machines using Proxmox VE.
• Automation: Ability to automate administrative tasks via scripting languages such as PowerShell, Bash, or Python.
• Desktop & Applications: Demonstrated ability to provide workstation support and deploy/troubleshoot COTS and GOTS applications.

Preferred Qualifications

• Experience leading teams through the design, implementation, and optimization of mission‑critical enterprise environments.
• Cisco Certifications: CCNA or CCNP.
• Additional CompTIA Certifications: Network+, Server+.
• Microsoft or Linux Certifications: Azure, Windows Server Hybrid Administrator, or RHCSA.
• Familiarity with security best practices and regulatory compliance frameworks (e.g., HIPAA, PCI, SOC 2, RMF).
• Strong background in provisioning, maintaining, and troubleshooting complex networks.
• Understanding of Risk Management Framework (RMF), STIG applications, and operating within highly regulated government IT environments.
• Experience with Splunk, BigFix, Fortinet, SharePoint.
• Experience in a leadership role.

Compensation Details: $120K-$150K The compensation range or hourly rate listed for this position is provided as a good-faith estimate of what the company intends to offer for this role at the time this posting was issued. Actual compensation may vary based on factors such as job responsibilities, education, experience, skills, internal equity, market data, applicable collective bargaining agreements, and relevant laws.

Benefits Overview: Our health and welfare benefits are designed to support you and your priorities.

• Health, dental, and vision insurance
• Paid time off and holidays
• Retirement benefits (including 401(k) matching)
• Educational reimbursement
• Parental leave
• Employee stock purchase plan
• Tax‑saving options
• Disability and life insurance
• Pet insurance

Note: Benefits may vary based on employment type, location, and applicable agreements. Positions governed by a Collective Bargaining Agreement (CBA), the McNamara‑O'Hara Service Contract Act (SCA), or other employment contracts may include different provisions/benefits.

Original Posting: 07/30/2026 - Until Filled

Amentum anticipates this job requisition will remain open for at least three days, with a closing date no earlier than three days after the original posting. This timeline may change based on business needs.

Amentum is proud to be an Equal Opportunity Employer. Our hiring practices provide equal opportunity for employment without regard to race, sex, sexual orientation, pregnancy (including pregnancy, childbirth, breastfeeding, or medical conditions related to pregnancy, childbirth, or breastfeeding), age, ancestry, United States military or veteran status, color, religion, creed, marital or domestic partner status, medical condition, genetic information, national origin, citizenship status, low‑income status, or mental or physical disability so long as the essential functions of the job can be performed with or without reasonable accommodation, or any other protected category under federal, state, or local law.

Learn more about your rights under Federal laws and supplemental language at Labor Laws Posters.

For more than 100 years, Amentum has tackled the world’s toughest challenges to deliver agile and steadfast solutions to the U.S. government and its allies. With more than 50,000 employees on all seven continents and in more than 60 countries, Amentum delivers a broad range of operational support services to meet the critical needs of our clients.

Our headquarters are in Chantilly, VA.

Find us online at https://www.amentum.com/