Agile Decision Sciences LLC is seeking a Linux System Administrator Senior with a minimum of a Secret clearance. We are committed to leveraging cutting-edge technology and innovative solutions to support the mission of the US Army Communications-Electronics Command (CECOM). As we continue to enhance our IT infrastructure and software capabilities, we are seeking highly skilled professionals to join our team in various key roles. Each position plays a crucial part in maintaining and advancing our environment, ensuring seamless operations and robust support for CECOM personnel worldwide.  This is a remote role. Must be U.S. based and be able to work Monday-Friday, 8 am to 5 pm EST. This position supports Linux Engineering Sustainment under ASRC Federal's CECOM SETA Support within the PEO EIS MSP, in direct support of the CECOM Army Software Integration Center (ASIC). The PEO EIS MSP ensures that the U.S. Army's Linux systems are secure, reliable, and capable of supporting mission-critical operations. As a Senior Linux System Administrator, you will lead the day-to-day administration, hardening, and modernization of complex enterprise Linux environments and play a key role in delivering ASIC software updates to deployed soldiers. Key Responsibilities Administer, maintain, and harden enterprise Red Hat Enterprise Linux (RHEL) environments across on-premises and AWS GovCloud infrastructure. Operate and troubleshoot high-availability architectures including Red Hat Pacemaker / Corosync clusters and load-balanced services. Lead patch management, system hardening, and STIG/ACAS compliance activities; coordinate vulnerability remediation across production fleets. Support ASIC software delivery workflows, including web-based deployment of software updates to deployed Army units. Develop and maintain Infrastructure as Code (IaC) and configuration management using Ansible, Terraform, or equivalent. Author and maintain automation scripts (Bash, Python) to streamline operational tasks, monitoring, and reporting. Collaborate with security, network, and application teams to support Authority to Operate (ATO) activities and Continuous Authorization processes. Serve as a senior technical resource - mentor junior administrators, lead troubleshooting bridges, and contribute to architecture and lifecycle decisions. Minimum Qualifications Bachelor's Degree in Computer Science, Computer Engineering, Information Systems, or a related technical discipline preferred. Four additional years of equivalent experience in lieu of degree will also be considered. Active Secret security clearance required or higher; ability to obtain and maintain TS/SCI strongly preferred. Minimum 5 years of hands-on Linux system administration experience, with at least 3 of those years in a senior-level or technical lead capacity. Demonstrated experience supporting mission-critical Linux environments in a DoD or federal setting. Experience administering and troubleshooting RHEL in both on-premise data centers and cloud environments. Proven ability to communicate technical strategies, risks, and recommendations clearly to both technical teams and customer stakeholders. DoD 8570/8140 compliant baseline certification (Security+ CE or higher) required at time of hire or within 6 months. Required Skills Expert-level Red Hat Enterprise Linux administration (RHEL 8 required; RHEL 9 strongly preferred). Experience operating RHEL workloads in AWS GovCloud, including EC2, S3, IAM, VPC, and EBS. Strong scripting and automation skills in Bash and Python; PowerShell a plus. Hands-on experience with Ansible (or equivalent configuration management - Puppet, Chef, Salt). Working knowledge of CI/CD tooling (GitLab CI, Jenkins, or similar) and Git-based source control workflows. Experience with system hardening, STIG application, ACAS scanning, and vulnerability remediation in DoD environments. Solid understanding of TCP/IP networking, DNS, LDAP/Active Directory integration, PKI, and SSH key management. Demonstrated problem-solving ability under operational pressure; excellent written and verbal communication. Linux-focused certification preferred (RHCSA, RHCE, or CompTIA Linux+). Desired Skills Familiarity with CECOM ASIC software delivery processes and web-based deployment to deployed Army units. Infrastructure as Code experience with Terraform or AWS CloudFormation. Experience with observability and SIEM tooling - Splunk, Elastic, Prometheus/Grafana. Knowledge of Zero Trust architecture principles and DoD ICAM. Experience performing RHEL major version upgrades (RHEL 7 → 8, RHEL 8 → 9) and Leapp-based migrations. Working knowledge of ServiceNow ITSM workflows (Incident, Problem, Change). Familiarity with ERP SAP environments running on Linux. Experience working in an Agile / Scrum framework. Red Hat Certified Engineer (RHCE), AWS Solutions Architect, or comparable advanced certification. Cybersecurity Requirements This position requires an understanding of software assurance and compliance with Application Security and Development Security Technical Implementation Guidelines (STIGs) applicable to the project. The selected candidate must be able to operate within DoD Risk Management Framework (RMF) processes and support Continuous Authorization (cATO) activities. Why ASRC?  As a wholly owned subsidiary of Arctic Slope Regional Corporation, an Alaska Native Corporation, we are inspired by the Iñupiat culture. We embrace stewardship and the idea of using every resource effectively; teamwork when striving to achieve goals and building a collaborative environment; integrity in adhering to high moral principles and professional standards; respect in welcoming and regarding the differing opinions, experiences, rights and traditions of others; accountability in that we meet our commitments and take responsibility for our results; and continuous improvement, always striving to make things better, raising the bar and staying humble. Advantages of Working at ASRC Federal: Purpose-Driven Careers: Join a company recognized as a: Certified Great Place to Work Military Times’ Best for Vets Employer Military.com’s Top 25 Veteran Employer Comprehensive Benefits: Insurance Coverage: Comprehensive plans for medical, dental, vision, life insurance, and short-term/long-term disability Paid Leave: Inclusive policies for bereavement, military obligations, and parental needs, along with 11 paid holidays annually Retirement Savings: A 401(k) plan with a generous company match and immediate vesting to help secure your financial future Incentives: Employee referral bonuses to reward you for helping grow the ASRC Federal Family Learning and Development: After 90 days of employment, regular full-time employees are eligible for our professional development program. This includes annual funding for: Pursuing Associate’s, Bachelor’s, or Graduate Degrees Obtaining industry-standard professional certifications Participating in professional certificate programs Covering registration fees for professional conferences Centers of Excellence: We established the Centers of Excellence to build, leverage and grow our technological capabilities, best practices and offer professional development for our technical teams.  They contain many Communities of Practice which are forums that offer a platform to share ideas, best practices, innovations, and to collaborate with technical peers.   Data Management: Applications will be reviewed in intervals. The first 15 candidates will be considered, followed by subsequent groups of 15.