Senior Linux System Administrator

Key ResponsibilitiesSystem Administration & Maintenance: Administer, configure, troubleshoot, and maintain production and non-production RHEL and Ubuntu Server VMs and physical servers.Security Hardening & Compliance: Maintain CIS-aligned hardening on Ubuntu systems, working within the agency's existing security stack, including Azure-native tooling such as Defender for Cloud and Azure Policy. Support compliance reporting and remediation using this stack.Patching & Lifecycle: Manage patching through Ubuntu Pro (Livepatch and Extended Security Maintenance) and APT, minimizing manual patch orchestration and unplanned downtime.Automation & Scripting: Write and maintain automation in Bash and PowerShell to support a mixed Linux and Azure environment. Familiarity with implementing Cron jobs and other scheduled automations.Azure & DevOps Integration: Familiarity and experience with on-prem Azure DevOps for source control, pipelines, and CI/CD supporting Docker configuration and deployment to a Linux environment.Containers & Secrets Management: Support Docker workloads running on standalone Linux VMs (outside of Kubernetes or Azure Container Instance clusters), including integrating containers with Azure Key Vault. Experience with using Azure Container Registry, including Push/Pull and vulnerability scanning.Identity & Access Management: Maintain and secure SSSD-based identity integration, including sudoers governance and PAM configuration.Storage & Filesystem Management: Manage LVM, filesystems (XFS/EXT4), and partition layout, including dedicated mounts such as /var, /tmp, and /var/log/audit, in line with CIS guidance.Audit Support: Collaborate with the cybersecurity team to support audit findings, logging through auditd, and ongoing security posture, using the existing security stack and Azure-native tooling as the primary audit trail.Required Qualifications & Technical Skills• 8+ years of hands-on Linux administration in enterprise or government environments, with deep expertise in current Ubuntu Server LTS releases.• Working knowledge of Azure as an operating environment for Linux VMs, including networking, managed identity, and Key Vault integration.• Experience with Azure DevOps, including pipelines, repositories, and CI/CD workflows involving Linux systems.• Experience with Docker on Linux, including secrets management approaches for containers running outside of managed clusters.• Advanced Bash scripting and working PowerShell proficiency for cross-platform automation.• Understanding of UFW, SSH hardening, AppArmor, and SSL/TLS certificate management.• Proficiency with systemd, kernel tuning via /etc/sysctl.conf, PAM, auditd, and log rotation.• Ability to work independently with limited dedicated Linux peer support, as part of a small, cross-functional IT and security team.Preferred Qualifications• Certifications: Canonical/Ubuntu certifications, CISSP, or CompTIA Security+. AZ-900 and/or AZ-104 preferred.• Healthcare or public sector experience, including state agency IT environments, MARS-E, HIPAA technical safeguards, or CMS security requirements.• Experience supporting development infrastructure with fast-changing workload requirements.