Linux System Administrator/Engineer

Crest Security Assurance•Newport, RI

8d•$125,000 - $130,000•Onsite

About The Position

We are seeking a motivated and mission-focused Linux Systems Engineer / Administrator to support advanced tactical and cybersecurity-focused systems in a dynamic Department of Defense environment. The ideal candidate will possess strong Linux systems administration expertise, hands-on cybersecurity experience, and a willingness to work across systems engineering, platform hardening, automation, and operational support activities. This role supports the engineering, security, integration, and sustainment of mission-critical systems operating in complex networked environments. Candidates should be comfortable collaborating with cross-functional engineering teams, participating in technical reviews, and contributing to secure systems modernization efforts.

Requirements

Significant experience with Linux systems administration in enterprise or mission-critical environments
Strong understanding of Linux networking
Strong understanding of Linux filesystems
Strong understanding of Privilege and identity management
Strong understanding of System hardening and STIG compliance
Strong understanding of Bash shell scripting
Strong understanding of Python programming
Strong understanding of Network enumeration
Strong understanding of Privilege escalation
Familiarity with CI/CD pipelines and DevSecOps concepts including Automated tooling, Unit testing, Static and dynamic application security testing (SAST/DAST)
Experience working in containerized environments using Kubernetes or equivalent orchestration tools
Ability to troubleshoot complex Linux systems and networking issues
Strong technical writing and verbal communication skills
Active Secret Security Clearance or eligibility for reinstatement
Experience managing and maintaining virtualized environments including virtual machine (VM) creation, configuration, administration, and lifecycle management
CompTIA Linux+ (Required)
Cybersecurity: 1 year (Required)
Systems Engineering: 2 years (Required)

Nice To Haves

Advanced Linux expertise including Filesystem administration and manipulation
Advanced Linux expertise including Encryption and key management
Advanced Linux expertise including SELinux administration
Advanced Linux expertise including ACL and IMA labeling
Experience supporting tactical networks, critical infrastructure, or defense systems
Experience working within a Scaled Agile Framework (SAFe) environment
Familiarity with undersea domain systems or submarine platforms
Prior experience supporting DoD cybersecurity initiatives or classified environments
Experience with virtualization technologies and VM management in enterprise or lab environments (VMware, KVM, VirtualBox, Hyper-V, or equivalent)
Linux Administration: 3 years (Preferred)

Responsibilities

Administer, maintain, and secure Linux-based systems in operational and development environments
Implement and maintain Linux system hardening in accordance with DISA STIGs and cybersecurity best practices
Manage firewall configurations, networking services, privilege management, and access controls
Support systems engineering efforts by evaluating and implementing engineering changes and cybersecurity enhancements
Develop and maintain shell scripts and Python-based automation solutions to improve operational efficiency and system reliability
Assist with deployment and sustainment of containerized applications using Kubernetes or similar orchestration platforms
Participate in CI/CD pipeline development and maintenance including automated testing, SAST/DAST integration, and deployment workflows
Support cybersecurity assessments, vulnerability remediation activities, and RED TEAM exercises
Analyze penetration testing results and recommend mitigation or remediation strategies
Collaborate with engineering, cybersecurity, and operations teams during trade studies, integration efforts, and technical reviews
Provide on-site technical support during testing events, system installations, and fleet or vendor visits as required
Maintain documentation related to system configurations, engineering changes, security controls, and operational procedures
Develop and maintain technical documentation including system procedures, engineering artifacts, implementation plans, test plans, and test reports
Support system integration and Test & Evaluation (T&E) activities through test planning, execution support, documentation, and reporting
Coordinate with engineering and cybersecurity teams to document system changes, validation activities, and remediation efforts