Senior Systems Admin - Linux, Automation & Security

The Johns Hopkins University Applied Physics Laboratory; Laurel (MD); On-site; USD 100,000 - 245,000; Full time

Job summary

The Johns Hopkins University Applied Physics Laboratory (APL) is seeking an experienced Senior Systems Administrator to support mission-critical systems in highly classified environments. This hands‑on role blends Linux depth with broad infrastructure responsibility, including Windows, virtualization, storage, and cybersecurity.

You will mentor teammates and drive secure, reliable services. Qualifications include 8+ years in systems administration (Linux strong), TS eligibility, and IAT II or

Qualifications

• Bachelor's degree in information technology, computer science, cybersecurity, or a related field, or 10+ years equivalent practical experience.
• 8+ years of progressively responsible systems administration experience, including substantial production Linux administration.
• Broad experience in at least three adjacent areas, such as Windows administration, virtualization, enterprise storage, networking, automation, HPC, cloud, or cybersecurity.
• Experience troubleshooting complex infrastructure issues and implementing sustainable corrective actions.
• Experience supporting classified, regulated, or other security‑controlled environments.
• Ability to communicate technical information clearly and work effectively across technical, security, and program teams.
• An active Top Secret clearance and the ability to obtain SCI access. U.S. citizenship is required.
• An IAT Level II certification, such as Security+ CE, or the ability to obtain one within the required timeframe.

Responsibilities

• Serve as a senior escalation point for complex issues involving operating systems, virtualization, storage, networking, hardware, and security.
• Provide advanced Linux administration across RHEL-based systems, including services, authentication, permissions, package management, performance, scripting, and hardening.
• Administer and integrate Windows Server, Active Directory, Group Policy, DNS/DHCP, VMware, Hyper-V, NetApp, enterprise storage, and HPC or cloud platforms.
• Plan and execute patches, upgrades, migrations, technology refreshes, and mature lifecycle management activities with minimal operational disruption.
• Monitor system performance, capacity, availability, and security; lead root-cause analysis and corrective actions.
• Configure and troubleshoot network connectivity, VLANs, switch ports, uplinks, and segmentation in coordination with network engineers.
• Implement STIGs, remediate vulnerabilities, and support RMF, ATO, audit, and continuous-monitoring activities.
• Improve reliability and efficiency through automation using Ansible, Python, PowerShell, or similar tools.
• Mentor administrators, lead small technical initiatives, and maintain clear runbooks, configuration records, and status updates.

Skills

Linux administration

Windows administration

Automation

Networking

Cloud

Cybersecurity

Education

Bachelor's degree in information technology, computer science, cybersecurity, or related field

10+ years equivalent practical experience

Master's degree (preferred)

Tools

VMware

Hyper-V

NetApp

Ansible

Python

PowerShell

Job description

The Johns Hopkins University Applied Physics Laboratory (APL) is seeking an experienced Senior Systems Administrator to support mission-critical systems in highly classified environments. This hands‑on role blends Linux depth with broad infrastructure responsibility, including Windows, virtualization, storage, and cybersecurity.

You will mentor teammates and drive secure, reliable services. Qualifications include 8+ years in systems administration (Linux strong), TS eligibility, and IAT II or