Infrastructure/System Administrator

Job Title: Infrastructure/System Administrator Job Category: Information Technology Time Type: Full time Minimum Clearance Required to Start: TS/SCI Employee Type: Regular Percentage of Travel Required: Up to 10% Type of Travel: Local * * * The Opportunity: CACI is seeking a Classified Systems Administrator to support and maintain mission-critical classified information systems within a secure environment. This position combines systems administration, systems engineering, cybersecurity, virtualization, and Information Assurance (IA) responsibilities to ensure the availability, reliability, security, and compliance of classified IT environments. The ideal candidate will bring hands-on experience administering Microsoft Windows Server infrastructure, virtualization technologies, enterprise applications, storage platforms, identity and access management, and cybersecurity tools. This individual will work across technical and security teams to maintain system performance, address vulnerabilities, support configuration changes, and ensure classified systems operate in accordance with applicable DoD, DCSA, and NISPOM requirements. Responsibilities:

• Install, configure, administer, maintain, and troubleshoot Microsoft Windows Server operating systems across classified environments.
• Manage virtualization platforms, including VMware, Microsoft Hyper-V, and Nutanix , ensuring system availability, performance, scalability, and security.
• Administer enterprise services and applications, including Microsoft Exchange and Microsoft SQL Server .
• Troubleshoot and resolve complex hardware, software, networking, operating system, application, and infrastructure issues across multiple classified networks.
• Monitor system health and performance, perform operating system patching, and implement vulnerability remediation and security mitigations using tools such as Nessus .
• Manage enterprise storage platforms, including Pure Storage, Dell PowerVault, and Synology appliances.
• Administer Microsoft Active Directory , including classified user account provisioning, access modifications, permissions, Group Policy, DNS, and DHCP in accordance with applicable security requirements.
• Maintain accurate inventory, configuration, and accountability records for classified IT assets, removable media, hardware, and peripheral equipment in accordance with DCSA requirements.
• Prepare and submit Security Impact Analysis (SIA) packages for proposed hardware, software, system, and configuration changes and coordinate required approvals prior to implementation.
• Support Information Assurance and cybersecurity activities associated with maintaining secure and compliant classified information systems.
• Provide Tier III technical support , perform root-cause analysis, resolve escalated technical issues, and communicate system status and risks to technical and program leadership.
• Mentor junior technicians and system administrators, share technical knowledge, and support the development of consistent system administration practices.
• Collaborate with cybersecurity, engineering, infrastructure, and program teams to identify technical risks and implement secure, sustainable solutions.
• Participate in scheduled after-hours maintenance, system upgrades, incident response, and outage support as mission requirements dictate. Qualifications: Required
• Active Secret security clearance .
• Bachelor's degree in Information Technology, Computer Science, Systems Engineering, Cybersecurity, or a related discipline, or equivalent combination of education, technical training, certifications, and professional experience.
• 7+ years of relevant Systems Administration, Systems Engineering, or related enterprise IT experience.
• CompTIA Security+ certification or another applicable DoD-approved cybersecurity certification.
• Extensive experience administering Microsoft Windows Server environments, including installation, configuration, patch management, system maintenance, troubleshooting, and performance optimization.
• Hands-on experience supporting virtualization technologies such as VMware, Hyper-V, and/or Nutanix .
• Experience identifying and remediating system vulnerabilities and implementing security mitigations using enterprise vulnerability management tools such as Nessus .
• Strong working knowledge of Microsoft Active Directory, Group Policy, DNS, DHCP, identity management, and access control .
• Experience supporting secure or classified enterprise IT environments and working within established cybersecurity and configuration management processes.
• Strong troubleshooting, analytical, critical-thinking, and problem-solving skills with the ability to diagnose complex infrastructure issues.
• Strong written and verbal communication skills with the ability to clearly communicate technical issues, risks, recommendations, and status to technical teams and leadership.
• Ability to work independently while collaborating effectively across systems administration, engineering, cybersecurity, Information Assurance, and program teams.
• Demonstrated commitment to continuous learning and maintaining technical expertise in evolving infrastructure and cybersecurity technologies. Desired
• Experience administering and supporting Microsoft SQL Server environments.
• Experience implementing, administering, and maintaining Splunk for system monitoring, log management, analysis, or security operations.
• Experience administering McAfee/Trellix endpoint security technologies.
• Experience implementing or managing enterprise backup and recovery solutions such as Veeam, NAKIVO, or Commvault .
• Experience supporting Information Assurance (IA) processes within classified environments.
• Experience with DoD, DCSA, and NISPOM security and compliance requirements.
• Experience supporting system accreditation, configuration management, vulnerability remediation, security documentation, or related compliance activities.
• Experience working in highly secure, mission-critical environments requiring strong system availability, documentation, accountability, and change-control practices.
• 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. Since this position can be worked in more than one location, the range shown is the national average for the position. The proposed salary range for this position is: $75,200-$158,100 CACI is an Equal Opportunity Emplo