Linux System Administrator

Linux System Administrator (Mid–Senior) — Onsite, Full Scope Clearance Required
Location: Herndon, VA — 100% Onsite
Employment Type: Full-time

Overview
We are seeking a mid–senior level Linux System Administrator with strong AWS Dev/Sec/Ops experience to join an operational engineering team supporting mission-critical systems. The position is fully onsite at a cleared facility and requires a current Full Scope security clearance. The ideal candidate brings hands-on Linux administration skills, cloud automation experience in AWS, a security-first mindset, and familiarity with CI/CD, infrastructure as code, and operational monitoring at scale.
Key Responsibilities
• Design, deploy, operate, and maintain Linux-based servers and clusters (RHEL/CentOS/Oracle Linux/Ubuntu) in development, test, staging, and production environments.
• Operate and secure AWS infrastructure components (e.g. EC2, VPC, IAM, EBS, S3, RDS, EKS, Lambda, CloudWatch).
• Implement and maintain infrastructure-as-code using tools such as CDK, CloudFormation, and Terraform.
• Develop and maintain automation and CI/CD pipelines (e.g. GitLab, ArgoCD) to include pipeline integration of security tooling (e.g. SonarQube, Anchore)
• Harden systems to meet DISA STIG, CIS benchmarks, or agency-specific security baselines; apply patches and security updates in a controlled manner.
• Perform system hardening, vulnerability remediation, and coordinate with security teams for incident response and forensics.
• Create, maintain, and improve monitoring, alerting, and logging solutions (ELK/Opensearch, Prometheus, Grafana, CloudWatch, Splunk).
• Troubleshoot and resolve performance, stability, and availability issues across infrastructure and services.
• Implement backup, disaster recovery, and business continuity procedures.
• Collaborate with developers, security engineers, and operations staff to design secure, scalable solutions.
• Maintain clear documentation, runbooks, and configuration management records.
• Participate in on-call rotations and provide after-hours support as needed.

Required Qualifications
• Current Full Scope security clearance at time of hire.
• 5+ years of experience administering Linux systems in production environments (mid–senior level).
• 3+ years of hands-on AWS experience architecting, deploying, and operating secure cloud solutions.
• Strong experience with configuration management and automation tools (Ansible, Puppet).
• Proven experience with Infrastructure-as-Code (Terraform or CDK/CloudFormation).
• Familiarity with container technologies and orchestration (Docker, Kubernetes/EKS/Karpenter, Helm).
• Solid scripting skills (Bash, Python, or similar) for automation and tooling.
• Active CI/CD pipeline implementation experience (GitLab, ArgoCD, SonarQube, Anchore).
• Experience with service mesh or advanced networking in Kubernetes.
• Experience with non-relational databases, such as MongoDB
• Knowledge of cloud security best practices, IAM, network security, encryption, and monitoring.
• Experience applying and validating security baselines such as DISA STIG or CIS Benchmarks.
• Excellent troubleshooting and problem-solving skills with an operations mindset.
• Strong communication skills and ability to work collaboratively with both in-house developers and end users to support delivery of end-to-end solutions.
• Must be able to work 100% onsite at a cleared facility and comply with site security policies.
Preferred / Nice-to-Have
• Familiarity with zero trust concepts and implementation experience.
• Experience with secrets management solutions (HashiCorp Vault, AWS Secrets Manager).
• Experience with geographically dispersed highly available cloud solutions
• Experience with hybrid cloud implementation
• Professional certifications such as RHCE, AWS Certified SysOps Administrator, AWS Certified DevOps Engineer.
• Prior experience supporting DoD or other federal agency information systems.