Senior Infrastructure Systems Administrator - Platforms

The Opportunity

Are you interested in continuing your career in Europe in a mission focused environment? CACI has established and upcoming positions throughout the European theater supporting multiple customers for the Department of Defense. We are looking for experienced, innovative and motivated IT Specialists to support enablement US EUCOM's mission objectives.

As a Senior Infrastructure Platforms Administrator on the Platforms team, you will serve as a senior operational contributor responsible for the administration, sustainment, and troubleshooting of enterprise infrastructure platforms across a STIG-compliant, multi-site DoD environment. Your core focus is execution: keeping production systems healthy, resolving complex issues efficiently, and delivering reliable day-to-day operations across Active Directory, Group Policy, DNS/DHCP, PKI/Certificate Services, SCOM, and related Windows infrastructure. What separates this role from a standard systems administrator position is cross-platform depth. Problems in this environment rarely stay in one technology lane. A DNS issue may surface as an AD authentication failure that traces back to a certificate expiration, and you are expected to follow that thread across boundaries without needing to escalate at every handoff. Major changes and break-fix actions require formal writeups, whether that is an Engineering Implementation Plan (EIP), an Engineering Design Plan (EDP), or an operational runbook submitted through GitLab. The goal is not documentation for its own sake but ensuring the team can learn from and replicate your work. While this role is primarily operational, you will support junior and mid-level administrators through over-the-shoulder guidance and by producing clear, reusable documentation that raises the team's baseline capability over time.

Responsibilities

• Active Directory Administration: Administer and support Active Directory services including user and group management, security configurations, GPO implementation, and cross-site replication troubleshooting.
• Windows Server Administration: Install, configure, and maintain Windows Server environments across multiple sites, ensuring performance, reliability, and STIG compliance.
• DNS/DHCP Management: Administer and troubleshoot AD-integrated DNS and DHCP services, including forward/reverse lookup zones, conditional forwarders, DDNS update workflows, and scope management.
• PKI and Certificate Services: Support enterprise PKI operations including certificate enrollment, renewal, CRL distribution, and OCSP responder health.
• Group Policy Operations: Implement, test, and troubleshoot Group Policy Objects across the enterprise. Participate in GPO rationalization and cleanup efforts using AGPM with Git-backed version control.
• Cross-Platform Troubleshooting: Trace complex issues across technology boundaries. When a problem spans AD, DNS, PKI, MECM, or networking layers, follow it end-to-end rather than escalating at each handoff.
• System Security and Compliance: Execute STIG remediation, support ACAS vulnerability remediation workflows, and maintain platform configurations aligned with DISA security baselines and CCRI readiness criteria.
• Monitoring and Incident Response: Monitor platform health using SCOM, Splunk, or equivalent tooling. Respond to alerts, diagnose root cause, and restore service with documented resolution steps.
• Documentation and Change Governance: Produce EIPs, EDPs, or operational runbooks in Markdown for major changes and complex break-fix actions. Submit documentation through GitLab merge requests for peer review.
• ServiceNow Queue Management: Work the ITSM ticket queue efficiently, prioritizing based on mission impact and SLA requirements. Maintain accurate ticket documentation including troubleshooting steps, resolution, and time accounting.
• Scripting and Automation: Use PowerShell to automate routine administrative tasks, reporting, and bulk operations. Familiarity with Python or Bash for cross-platform scripting is a plus.
• Collaboration: Work closely with cybersecurity, networking, architecture, and project management teams to ensure platform changes are coordinated and compliant with mission requirements.
• Team Support: Provide over-the-shoulder guidance and technical support to junior and mid-level administrators. Produce clear runbooks and decision trees that enable less experienced team members to handle routine operations independently

The successful candidate must be able to communicate clearly and succinctly both written and orally, and present products and ideas in a business-like manner. The candidate will be required to work in dynamic fast-paced environments that require team interaction and coordination of efforts. The candidate must be experienced in interfacing with both client managers and system users. The Senior Infrastructure Platforms Administrator is expected to work independently on assigned tasks with minimal oversight. You will receive prioritization and scoping from the Platforms Lead but are expected to own execution, documentation, and follow-through without step-by-step direction. The balance of work in this role is roughly split between planned project deliverables, operational sustainment, and unplanned incident response, and you must be comfortable managing that balance day to day.

Qualifications

Required

• Bachelor's degree in Computer Science, Information Technology, or a related field, OR 7+ years of directly relevant enterprise infrastructure experience qualifying under TESA.
• Active TS/SCI security clearance.
• Minimum 5 years of experience in Windows systems administration with demonstrated depth across Active Directory, Group Policy, DNS/DHCP, and PKI/Certificate Services in multi-site environments.
• Demonstrated ability to troubleshoot complex, multi-system issues that span technology boundaries rather than staying siloed in a single platform area.
• Experience producing operational documentation, runbooks, or technical writeups that capture not just actions taken but rationale and replication steps.
• Moderate to strong PowerShell scripting skills for automation, reporting, and bulk administrative operations.
• Experience with Git/GitLab for version-controlled documentation and merge-request-based workflows.
• Experience operating in DISA STIG-hardened environments with practical knowledge of vulnerability remediation and ACAS scan workflows.
• Familiarity with ServiceNow or equivalent ITSM platforms for ticket management, change requests, and incident tracking.
• Familiarity with network protocols and services (DNS, DHCP, TCP/IP) and virtualization technologies (VMware, Hyper-V).
• Baseline familiarity with Enterprise Linux (Red Hat), sufficient to understand cross-platform dependencies and coordinate with Linux-focused engineers on the team.
• CompTIA CASP+/SecurityX, CISSP, or equivalent DoD 8570/8140 IAT Level III certification.

• Ability to work OCONUS at a U.S. military installation in Stuttgart, Germany.

Desired

• Familiarity with Microsoft Endpoint Configuration Manager (MECM/SCCM), SCUP, and App-V for endpoint management and application packaging.
• Experience with CyberArk Privileged Access Management at an awareness level, understanding vault operations and credential rotation concepts.
• Exposure to Red Hat Satellite, Ansible Automation Platform, or basic Ansible playbook usage.
• Familiarity with Citrix ADC (NetScaler) for load balancing and authentication proxy configurations.
• Experience with SCOM, Splunk, or SolarWinds for enterprise monitoring and alerting.
• Familiarity with SQL Server administration in support of enterprise applications.
• Knowledge of cloud platforms (Azure, AWS) and containerization technologies (Docker, Kubernetes).
• Red Hat Certified System Administrator (RHCSA) or Microsoft infrastructure certifications.
• Experience supporting Combatant Command (CCMD) or Joint Service environments.

Personal Attributes

• Strong analytical and problem-solving skills. Follows the thread across systems rather than closing out what you can and punting the rest.
• Takes ownership of assigned work. Does not require follow-up to complete tasks, update tickets, or produce documentation.
• Communicates proactively. Flags blockers, risks, and status without being asked.
• Self-motivated with the discipline to balance ticket queue work, project tasks, and unplanned incidents without dropping accountability on any of them.
• Comfortable asking questions and seeking guidance from senior engineers and the Platforms Lead when encountering unfamiliar territory.
• Produces documentation as a natural part of completing work, not as an afterthought.

What You Can Expect:

 A culture of integrity.

At CACI, we place character and innovation at the center of everything we do. As a valued team member, you’ll be part of a high-performing group dedicated to our customer’s missions and driven by a higher purpose – to ensure the safety of our nation.

An environment of trust.

CACI values the unique contributions that every employee brings to our company and our customers - every day. You’ll have the autonomy to take the time you need through a unique flexible time off benefit and have access to robust learning resources to make your ambitions a reality.

A focus on continuous growth.

Together, we will advance our nation's most critical missions, build on our lengthy track record of business success, and find opportunities to break new ground — in your career and in our legacy.

Pay Range:

There are a host of factors that can influence final salary including, but not limited to, geographic location, Federal Government contract labor categories and contract wage rates, relevant prior work experience, specific skills and competencies, education, and certifications. Our employees value the flexibility at CACI that allows them to balance quality work and their personal lives. We offer competitive compensation, benefits and learning and development opportunities. Our broad and competitive mix of benefits options is designed to support and protect employees and their families. At CACI, you will receive comprehensive benefits such as; healthcare, wellness, financial, retirement, family support, continuing education, and time off benefits.

The proposed salary range for this position is: