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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Systems Administrator III - Windows / Linux / Enterprise Infrastructure - **Company:** Goal-Oriented Human Performance Technologies, LLC - **Location:** Portsmouth, VA, United States - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Microsoft Windows, Active Directory, Computing Platforms, User Authentication, Bash Shell, Network Operating System (NOS), Software as a Service, Configuration Management, Software Documentation, Cyber Security, Computer Programming, System Configuration, Dynamic Host Configuration Protocol, Linux, Domain Name System (DNS), Monitoring of Systems, Identity and Access Management, Information Systems Security Architecture Professional, Linux System Administration, Linux Commands, Linux Servers, Windows Servers, Performance Tuning, Windows PowerShell, Red Hat Enterprise Linux, Ansible, Server Administration, Software Deployment, User Provisioning Software, Virtualization Technology, Software Vulnerability Management, Enterprise Software Applications, Git, Information Technology, Performance Monitor, Patch Management, Data Management, CIS Benchmarks, Server Operating Systems & Platforms, User Accounts, Vmware - **Published:** October 14, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=7a7094f9ffb2762b ## About the Role Education and Experience Candidates must meet one of the following qualification pathways: Option 1 Bachelor's degree in: * Computer Science * Computer Programming * Network Engineering And a minimum of six (6) years of system administration experience. OR Option 2 Certificate from an accredited Community or Technical College in System Administration. And a minimum of eight (8) years of system administration experience. Additional Training Successful completion of additional training in one or more leading network operating systems, equipment, and protocols within two (2) years of task order solicitation, as required by the contract. Required Certification A current Certified Information Systems Security Professional (CISSP) certification or equivalent certification is required. Additional information assurance certifications may be required at the task order level. Required Technical Experience * Operating system installation and maintenance. * Enterprise systems administration. * System configuration management. * User account and profile administration. * Operating system troubleshooting. * Hardware and software evaluation. * Monitoring compliance with system standards. * Technical documentation. Security Requirements * U.S. Citizenship required for eligibility for the required security clearance. * Secret security clearance required. * Ability to maintain the required clearance throughout employment. Preferred Qualifications Operating Systems Experience with: * Microsoft Windows Server. * Red Hat Enterprise Linux (RHEL). * Enterprise Linux administration. * Windows and Linux command-line administration. Enterprise Infrastructure Familiarity with: * Active Directory. * Group Policy. * DNS. * DHCP. * Enterprise storage systems. * Virtualized server environments. * System monitoring solutions. * Backup and recovery platforms. * Authentication and access management systems. Security and Compliance Experience supporting: * DISA Security Technical Implementation Guides (STIGs). * Security configuration baselines. * Vulnerability remediation. * Risk Management Framework (RMF) activities. * Government cybersecurity assessments. * Configuration management and change control. Automation and Administration Tools Experience with: * PowerShell. * Bash. * Ansible. * VMware or comparable virtualization technologies. * Git. * Enterprise monitoring tools. * Automated patch management solutions. Government Experience * Experience supporting U.S. Coast Guard, DHS, or DoD infrastructure. * Experience with C4IT systems. * Experience working in security-controlled government computing environments. * Experience supporting system accreditation and authorization activities. Core Technical Competencies * Operating system administration. * Server configuration. * Systems troubleshooting. * User and access management. * Systems monitoring. * Performance optimization. * System security. * Patch management. * Configuration management. * Backup and recovery. * Technical documentation. * Infrastructure sustainment. Core Competencies The successful candidate will demonstrate: * Advanced troubleshooting capabilities. * Strong analytical and problem-solving skills. * Ability to manage multiple technical priorities. * Strong attention to detail. * Effective written and verbal communication. * Independent technical judgment. * Commitment to system security and operational availability. * Ability to coordinate across engineering and cybersecurity teams. * Strong documentation and procedural discipline., License/Certification: * and active U.S. gov't security clearance (Required) * CISSP certification or equivalent (Required) ## Description The successful candidate will possess extensive experience administering operating systems, managing system configurations, maintaining system security, and supporting complex computing environments. This position requires strong technical troubleshooting capabilities, knowledge of enterprise infrastructure operations, and the ability to independently diagnose and resolve complex system problems. The System Administrator III may also coordinate system administration activities across multiple systems and provide technical guidance to junior administrators and engineering personnel., Systems Administration * Install, configure, maintain, and troubleshoot server operating systems and supporting software. * Administer enterprise computing systems in accordance with approved operating procedures. * Manage system configuration settings and operating environments. * Monitor server health, availability, performance, and capacity. * Perform operating system upgrades, software installations, and configuration changes. * Administer system services and associated infrastructure components. * Evaluate and recommend hardware and software improvements. * Support system deployment, modernization, and sustainment activities. Windows and Linux Administration * Administer Windows and Linux server environments as assigned. * Configure operating system services, permissions, accounts, and system resources. * Diagnose operating system errors and service failures. * Analyze system logs and performance metrics. * Perform system updates and approved maintenance activities. * Support application hosting and operating system compatibility. * Troubleshoot resource utilization, service availability, and operating system performance. Identity and Account Administration * Administer user accounts, access permissions, and system profiles. * Implement account management policies. * Support user provisioning, modification, and deactivation. * Troubleshoot authentication and authorization issues. * Maintain access controls consistent with approved security policies. * Support periodic access reviews and account audits. System Security and Compliance * Implement approved system security configurations. * Monitor compliance with applicable technical and security standards. * Apply authorized security updates and operating system patches. * Support vulnerability remediation activities. * Coordinate with cybersecurity personnel to address security findings. * Maintain system configuration documentation supporting cybersecurity compliance. * Support security assessments, audits, and authorization activities. * Implement system hardening configurations in accordance with approved security baselines. Performance Monitoring and Troubleshooting * Monitor system health, performance, storage utilization, and operational status. * Investigate recurring system errors, outages, and degradation. * Perform root cause analysis of technical incidents. * Develop corrective action recommendations. * Coordinate incident resolution with engineering, network, and application support teams. * Support service restoration and operational recovery. * Document technical findings and recurring issues. Backup and Recovery * Administer or support system backup and recovery operations. * Verify successful execution of backup activities. * Support restoration testing. * Maintain recovery procedures and technical documentation. * Participate in contingency planning and system recovery exercises. Configuration and Change Management * Maintain accurate system configuration records. * Support approved configuration changes and system maintenance releases. * Evaluate operational impacts of proposed modifications. * Maintain system inventory and configuration baselines. * Participate in change reviews and implementation planning. * Document configuration changes and technical procedures. Technical Coordination * Coordinate system administration activities across multiple systems. * Provide guidance to junior system administrators. * Collaborate with cybersecurity engineers, software developers, network engineers, and Government personnel. * Participate in technical meetings and engineering reviews. * Support planning and execution of infrastructure upgrades. * Escalate system risks and operational concerns as appropriate., The successful candidate will: * Maintain reliable and secure computing environments. * Identify and resolve system problems efficiently. * Ensure systems comply with established configuration standards. * Support consistent application of security requirements. * Maintain accurate system documentation. * Minimize operational disruption during system maintenance. * Coordinate system administration activities effectively across multiple environments.