System Administrator
About The Position
Leidos' Corporate Information Security Office, reporting through the Digital sector, is seeking a System Administrator to support various classified environments. The role is responsible for maintaining, securing, and supporting a complex classified information system and ensuring compliance with security protocols and regulations. All work will be performed on site in the San Diego, California office. Candidates must hold a current, active DoD Top Secret clearance; the position also requires sustained ability to be cleared to Special Access Programs (SAP) and ability to obtain a polygraph. The role combines system administration and security duties to protect information and maintain security controls across an entire system, site, or program. The administrator supports Windows and Linux environments, enterprise networking and storage, security compliance, vulnerability remediation, system monitoring, backups, change management, technical documentation, and end-user support. The position collaborates with ISSOs, ISSMs, engineering personnel, and program stakeholders to support operations and security authorization activities.
Requirements
- Bachelor’s degree and 4–8 years of experience, or equivalent relevant industry-standard experience and certifications in lieu of a degree.
- Must be a U.S. citizen.
- Must currently hold an active Top Secret security clearance and have sustained ability to be cleared to SAP and ability to obtain a polygraph.
- Must have a current DoD 8570 IAT Level II or higher certification, such as CompTIA Security+.
- Experience administering, configuring, troubleshooting, and maintaining Windows and Linux operating systems in an enterprise environment, including workstations, Active Directory, DNS, and Group Policy.
- Experience supporting SAP environments, including familiarity with the Joint Special Access Program Implementation Guide, RMF, and system authorization lifecycle requirements.
- Working knowledge of enterprise networking concepts and switching technologies, including TCP/IP, VLANs, subnetting, RADIUS, firewall rules, and network troubleshooting.
- Experience with compliance tools including DISA SCAP, Evaluate STIG, Tenable Nessus, and Trellix; ability to interpret scan results, identify security efficiencies, implement corrective actions, and maintain compliance documentation.
- Experience configuring, managing, and troubleshooting enterprise storage and file-sharing technologies, including iSCSI, SMB, and NFS.
- Understanding of Windows NTFS permissions, Linux file permissions, access control lists, and secure storage provisioning.
- Knowledge of change management processes, configuration baselines, documentation standards, and system lifecycle procedures; ability to plan, document, and execute changes while minimizing operational impact and maintaining security compliance.
- Ability to independently diagnose and resolve moderately complex hardware, software, operating system, and network issues.
- Experience with software installation, system updates, remote administration, and routing maintenance within controlled environments.
- Ability to develop and maintain technical documentation, standard operating procedures, work instructions, and system configuration records.
- Experience collaborating with engineering, cybersecurity, and program stakeholders to support operational requirements.
Nice To Haves
- RedHat Certified System Administrator (RHCSA) certification.
- Experience developing, modifying, and executing PowerShell, Bash, or Ansible scripts or playbooks for system deployment, configuration management, patching, security, compliance, and operational repeatability.
- Experience administering virtualized environments, working with High Performance Computing (HPC), and managing enterprise backup and recovery solutions.
Responsibilities
- Administer, maintain, and troubleshoot Windows and Linux workstations and servers in a mixed operating system environment.
- Manage Active Directory services, including user and computer accounts, Group Policy Objects, DNS, and system authentication.
- Perform system maintenance, software installations, patching, configuration updates, and hardware troubleshooting.
- Configure and maintain network infrastructure, including switches, VLANs, IP addressing, firewall rules, and network connectivity.
- Administer enterprise storage and file-sharing services, including SMB, NFS, iSCSI, file-system permissions, and access controls.
- Implement and maintain system security configurations in accordance with DISA STIGs, JSIG, RMF, and organizational cybersecurity requirements.
- Conduct vulnerability assessments and compliance scans using tools such as DISA SCC, Evaluate-STIG, and Tenable Nessus; remediate findings and document corrective actions.
- Develop and maintain PowerShell, Bash, or Ansible scripts to improve administration efficiency, configuration consistency, and repeatability.
- Monitor system health, performance, storage utilization, backup operations, and security logs to identify and resolve operational issues.
- Support system backup, recovery, and data protection activities.
- Follow change management processes by documenting, coordinating, and implementing approved system modifications.
- Develop and maintain technical documentation, system configurations, network diagrams, and standard operating procedures.
- Collaborate with ISSOs, ISSMs, and engineering personnel on continuous monitoring, security assessments, and authorization activities.
- Provide technical support to end users, troubleshoot reported issues, and coordinate with program stakeholders to minimize disruptions.
- Assist with hardware refreshes, system deployments, technology upgrades, and infrastructure modernization initiatives.
- Perform other duties as assigned.
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What This Job Offers
Job Type
Full-time
Career Level
Mid Level
