Sr. Linux Systems Administrator (Top Secret)

RedLine Performance Solutions (RedLine) has been in the HPC solutions engineering services business for over 26 years and is consistently determined to keep the "bar of excellence" quite high for new hires. This enables RedLine to accomplish what other firms cannot and promotes a high level of staff retention. We offer services ranging from full life cycle HPC systems engineering to remote managed services to HPC program analysis. RedLine is looking for an Sr. Linux Systems Administrator to join us. The successful candidate will be responsible for the architecture, operation, and maintenance of a critical High‑Performance Computing (HPC) and Kubernetes infrastructure. This role requires a deep understanding of cloud‑native technologies, robust security practices, and large‑scale system administration to maintain a secure and reliable platform. An active DoD Top Secret security clearance is a requirement to apply, as are current Linux+ and Security+ (or equivalent) certifications. This position is on‑site at the customer location in Aberdeen, Maryland. Relocation may be considered. This full‑time position offers a full benefits package including paid time off, 401k match, and health care benefits. Job Responsibilities: Kubernetes platform architecture and operations Design, deploy, and operate highly available RKE2 Kubernetes clusters, including multi‑control‑plane environments with stable etcd quorum Manage Kubernetes versioning upgrades and compatibility, along with cluster certificate authorities and trust chains Oversee complete lifecycle of Kubernetes nodes (cordon, drain, replacement) and operate container runtimes like containerd Tune kubelet behavior, manage resource pressure, and ensure consistent node configuration across all environments Networking, Security, and Identity Design and operate Kubernetes networking (CNI), implement network policies for workload isolation, and manage ingress controllers and DNS configurations Implement and enforce security best practices, including RBAC, admission controls, pod security standards, secrets management, and audit logging Perform routine systems administration and apply necessary STIGs and OS maintenance to ensure compliance for CUI‑level operations Integrate Kubernetes with enterprise identity services (LDAP/FreeIPA) and implement SSO with support for CAC/MFA Data, CI/CD, and Reliability Design and operate Kubernetes storage solutions using CSI drivers (Lustre, Weka), manage persistent volumes, and integrate S3 object storage Operate and maintain CI/CD infrastructure, including GitLab and container registries (Harbor, Artifactory), to support developer workflows Implement comprehensive monitoring, logging, and alerting. Lead incident response, perform capacity planning, and maintain operational runbooks Architect for high availability, define RPO/RTO, and implement robust backup, restore, and failover procedures for all stateful services Integrate Kubernetes workloads with HPC schedulers like Slurm/PBS and enable seamless, secure job submission and identity mapping between platforms. Required Skills Proven experience in systems administration, particularly in Linux‑based environments Extensive hands‑on experience designing, building, and operating production Kubernetes clusters Deep understanding of Kubernetes networking, security principles (RBAC, Network Policy, Pod Security Standards), and storage (CSI) Strong knowledge of container runtimes and the full node lifecycle Experience integrating applications and platforms with identity management systems like LDAP or FreeIPA Familiarity with operating CI/CD pipelines and associated tools (e.g., GitLab, Artifactory, Harbor) Preferred Skills Specific experience with RKE2 is highly desirable Experience working in secure, compliance‑driven environments (e.g., CUI, DoD) Knowledge of integrating Kubernetes with HPC schedulers (Slurm, PBS) and high‑performance storage (Lustre, Weka) Proficiency with observability stacks for monitoring, logging, and alerting Experience with Infrastructure as Code (IaC) and configuration management toolsDemonstrated ability to design and test high‑availability and disaster recovery plans. Total Rewards Competitive salary band: $140,000 – $180,000/year dependent on experience and relocation needs Medical, dental & vision coverage with substantial company contribution Company funded Healthcare Reimbursement Account (HRA) Paid time off (PTO) + 11 paid holidays Company Match 100% immediately vested retirement savings (401k) Employee wellness programs & gym discounts Employee assistance & concierge services Professional development resources To learn more about what makes RedLine a great place to work, please visit our website at #J-18808-Ljbffr