Top Senior System Administrator Jobs

Provides senior-level administration and technical leadership for secure DoD enterprise IT environments. Responsibilities include managing Windows servers, Active Directory, SCCM, virtualization, storage, backup and recovery, enterprise services, patching, vulnerability remediation, DISA STIG implementation, compliance documentation, and troubleshooting. Coordinates with government, cybersecurity, network, application, and service-provider teams to maintain system availability, performance, security, and mission continuity.

Provides senior-level administration and technical support for classified and unclassified DoD enterprise systems. Responsibilities include managing Windows servers, Active Directory, SCCM, virtualization, storage, backups, enterprise services, vulnerability remediation, STIG implementation, and compliance documentation. Coordinates with government, cybersecurity, network, and service-provider teams; troubleshoots complex infrastructure issues; supports audits, ATO activities, disaster recovery, and mission continuity. The role is fully on-site and requires an active Secret clearance.

Provides senior technical leadership for Windows server and enterprise infrastructure administration in classified and unclassified DoD environments. Responsibilities include Active Directory, SCCM, virtualization, storage, backup and recovery, patching, vulnerability remediation, STIG implementation, system troubleshooting, compliance documentation, ATO support, and coordination with government, cybersecurity, network, and service-provider teams.

Provides senior technical leadership for Windows and enterprise systems administration in classified and unclassified DoD environments. Responsibilities include managing Active Directory, SCCM, virtualization, storage, backup and recovery, enterprise services, patching, vulnerability remediation, DISA STIG implementation, compliance documentation, and troubleshooting. Coordinates with Government, cybersecurity, network, and service-provider teams while supporting system availability, audits, ATO requirements, disaster recovery, and mission continuity.

Provides senior technical leadership for Windows server and enterprise IT administration in classified and unclassified DoD environments. Responsibilities include Active Directory, SCCM, virtualization, storage, backup and recovery, endpoint management, patching, STIG implementation, vulnerability remediation, compliance documentation, troubleshooting, and coordination with cybersecurity, network, government, and service-provider teams. The role is fully on-site at Fort Eustis, Virginia and supports mission continuity, audits, ATO activities, and after-hours operational requirements.

Provides senior technical leadership for Windows server and enterprise infrastructure administration in classified and unclassified DoD environments. Responsibilities include Active Directory, SCCM, virtualization, storage, backup and recovery, vulnerability remediation, STIG implementation, compliance documentation, troubleshooting, system optimization, and coordination with government, cybersecurity, network, and service-provider teams. The role is fully on-site in Beaumont, Texas, and requires an active Secret clearance.

Provides senior systems administration and technical leadership for classified and unclassified DoD environments. Responsibilities include managing Windows servers, Active Directory, SCCM, virtualization, storage, backups, enterprise services, patching, vulnerability remediation, STIG implementation, troubleshooting, documentation, compliance artifacts, and disaster recovery. Coordinates with government, cybersecurity, network, and service-provider teams to maintain system availability, security, performance, and mission continuity. The position is fully onsite in Jacksonville, Florida.

Administer and support Windows servers, Active Directory, Citrix XenDesktop, Exchange, VMware infrastructure, firewalls, VPN, NAC, backups, and patch management across a multi-site federal environment. Provide Tier 1–3 support, perform system builds, upgrades, migrations, testing, and security remediation, and maintain technical documentation and disaster recovery plans. The role requires Public Trust eligibility, U.S. citizenship, and substantial systems administration experience.

Manage and maintain enterprise outbound dialer systems (Alvaria/Noble), ensure performance and compliance, troubleshoot production issues, integrate with CRM/voice infrastructure, run SQL-based analysis, support upgrades, and provide after-hours/business continuity support.

Support an IC-wide mission environment as a senior Linux Systems Administrator/Engineer. Require 10+ years Linux (CentOS/RHEL) experience, JBoss/Wildfly administration, VMware VM creation/operation, and Security+ certification. Desired skills include Red Hat Ansible, storage, networking, security compliance, authentication, shell/Python scripting, physical server administration, Oracle DB/DBA familiarity, JSON, and possession of/eligibility for high-level clearances.

Support an Intelligence Community mission environment as a senior Linux system administrator/engineer. Administer CentOS/RHEL systems, install/configure/maintain JBoss/Wildfly, manage VMware VMs, ensure security/compliance, perform scripting (Shell/Python), support storage, networking, authentication, physical servers, and occasional Oracle/DBA tasks. Must meet clearance and shift availability requirements.

Provide support for the design, configuration, and deployment of Windows Server environments, including virtualization and disaster recovery solutions.

The Senior System Administrator will design, configure, and support Windows Server environments, manage virtualization, and implement disaster recovery strategies.

Ensure immediate response to outages, support mainframe systems, analyze and resolve systems problems, and monitor software and hardware performance.

Provides senior Windows systems administration, operations, maintenance, monitoring, and infrastructure support across virtualized Windows and Linux environments. Manages VMware clusters, Active Directory, DNS, GPOs, SCCM, Exchange, patching, vulnerability remediation, IAVAs, security scans, and system configuration. Supports network and data center infrastructure, resolves hardware and software issues, documents activities, communicates outages, implements enhancements, and participates in on-call support within an Agile environment.

Administer and improve hybrid, multi-cloud infrastructure across Windows, Linux, networking, identity, security, and endpoint environments. Troubleshoot advanced routing and connectivity, manage NAC and IAM, automate provisioning and infrastructure changes, remediate vulnerabilities, support compliance audits, resolve complex escalations, and maintain documentation. Collaborate with business teams to improve IT processes, tooling, reliability, security, and end-user experience.

Senior system administrator responsible for Windows server and Active Directory architecture, STIG hardening and GPO implementation, large-scale data center operations, migrations (physical-to-virtual), enterprise backup management, and automation using VB/PowerShell within multi-tenant enterprise environments.

Lead LogiCole system administration for Air Force DMLSS: manage a system administration team, oversee project management, technical support, QA, staffing, scheduling, reporting, and risk. Provide hands-on administration, monitor servers and fiscal processes, support electronic catalogs and strategic sourcing, and protect confidential information.

Lead senior technical engineer for full-lifecycle infrastructure and sustainment of the FMWorkFlow environment. Responsibilities include Windows/Linux administration, Active Directory and service-account engineering, Nutanix virtualization, performance/capacity analysis, patch and configuration baseline management, backup/recovery and resilience, cross-stack integration with DB2/WebSphere and cybersecurity, Level III escalation, RMF/STIG compliance, and mentoring junior administrators.

Lead systems administrator for classified DoD/AF environments responsible for design, implementation, security, maintenance, and optimization of Windows/Linux, virtualization, container, and cloud infrastructure. Ensure RMF/DISA STIG compliance, perform vulnerability assessments, support SCI/SAP networks, automate infrastructure tasks, and lead/mentor technical staff while interfacing with government stakeholders.

Provide desktop, server, and network administration for mission and analytic networks, including application support, server administration, user account management, and basic LAN infrastructure support.

Administer and maintain Linux (RHEL/CentOS/Ubuntu) and Windows Server environments (AD, Group Policy); automate tasks with Python/Bash/PowerShell; monitor and troubleshoot systems; manage virtualization (VMware/Hyper-V), backups, security, user accounts, and documentation while collaborating with infrastructure and application teams.

The Senior System Administrator will oversee the administration and security of Linux systems, manage updates, and ensure operational stability in cloud environments.

Senior System Administrator responsible for engineering, administering, and supporting enterprise endpoint environments. Duties include deploying and maintaining Windows/macOS endpoints, virtual desktop and cloud-based platforms, implementing security controls and compliance, troubleshooting complex issues, automating tasks with PowerShell, participating in endpoint modernization (Intune, Autopilot, Windows 365, AVD), and working with Security, Infrastructure, and Service Desk teams to ensure stable, secure endpoint operations.

Lead administration and support of corporate Microsoft infrastructure, VDI/RDS access platforms, virtualization, storage, backups, and cloud services. Perform AD domain/forest migrations, replace legacy VDI and load‑balancing stacks, maintain documentation, resolve incidents to SLA, participate in projects and on‑call rotation, and collaborate with NOC, InfoSec, DevOps, and L2 teams.