Join a team that powers critical infrastructure and keeps mission-essential systems running securely, efficiently, and reliably. SAIC is seeking a skilled Linux Systems Administrator who thrives in complex enterprise environments and enjoys solving challenging technical problems across Linux, virtualization, and infrastructure platforms. In this role, you'll be a key member of the systems engineering team, responsible for the health, performance, security, and lifecycle management of our Linux-based infrastructure. You'll work with modern virtualization technologies, support enterprise-scale environments, implement automation, and help drive continuous improvement across our server and infrastructure ecosystem. What You'll Do: • Administer and maintain enterprise Linux environments, with a primary focus on Red Hat Enterprise Linux (RHEL) • Ensure system availability, performance, and security through proactive monitoring, troubleshooting, patching, and upgrades • Support and manage VMware vSphere and VMware Cloud Foundation (VCF) infrastructure • Implement and maintain security best practices, including CIS and STIG hardening standards • Troubleshoot and resolve infrastructure, application, operating system, connectivity, and security issues across on-premises environments • Monitor and optimize system resources including CPU, memory, storage, and overall server performance • Manage local repositories and coordinate operating system patching and lifecycle activities • Collaborate with infrastructure and systems teams on architecture, deployment, and operational initiatives • Develop and enhance automation through scripting and configuration management tools • Support Microsoft-based services and technologies, including Active Directory, DNS, DHCP, and related infrastructure components • Contribute to ongoing modernization efforts and continuous improvement across the enterprise technology stack • Experience providing systems administration support within mixed Microsoft Windows and Red Hat Enterprise Linux (RHEL) environments • Hands-on experience installing, configuring, administering, and troubleshooting Linux operating systems • Experience monitoring Linux infrastructure health, performance, and availability, and proactively resolving issues • Experience troubleshooting and resolving application, infrastructure, connectivity, and security issues in on-premises environments • Experience diagnosing and remediating server performance issues involving CPU, memory, storage, and system resources • Experience implementing Linux security hardening using CIS Benchmarks and/or STIG requirements Experience maintaining local repositories and performing system patching, updates, and lifecycle management activities • Experience supporting VMware vSphere and/or VMware Cloud Foundation (VCF) environments • Experience performing general systems administration and infrastructure support tasks across multiple technology platforms • Experience collaborating with infrastructure and systems engineering teams to support enterprise environments • Experience administering Microsoft infrastructure services, including Active Directory, DNS, DHCP, and related network services • Experience supporting desktop and workstation hardware • Experience implementing and managing Role-Based Access Control (RBAC) within multi-tenant environments • Experience developing or maintaining automation through scripting • Ability to support multiple priorities in a dynamic enterprise IT environment Preferred Qualifications: • Red Hat Certified System Administrator (RHCSA) and/or Red Hat Certified Engineer (RHCE) certification • Experience with Ansible, Puppet, or similar configuration management and automation tools • Working knowledge of Windows 11, Windows Server, VMware vCenter Server Appliance (VCSA), and VMware Cloud Foundation (VCF) • Working knowledge of enterprise infrastructure hardware, appliances, and supporting technologies • Experience performing Windows Server installation, configuration, patching, upgrades, migrations, and ongoing administration • Experience supporting enterprise virtualization, server infrastructure, and hybrid technology environments