Classified Systems Administrator and ISSO

CACI International Inc.; Herndon (VA); On-site; USD 104,000 - 218,000; Full time

Job summary

CACI International Inc. in Herndon, Virginia, seeks a Classified Systems Administrator and ISSO to support and maintain mission-critical classified information systems in a secure environment.

This role blends systems engineering, cybersecurity, virtualization, and IA duties to ensure reliability, security, and compliance. The ideal candidate will manage Windows Server infrastructure and virtualization (VMware, Hyper-V, Nutanix), administer enterprise services, and support DoD/NISPOM compliance.

Qualifications

• 7+ years of Systems Engineering and Systems Administration experience.
• Active Secret clearance required.
• Experience administering Windows Server environments with patching and performance tuning.
• Hands-on virtualization experience with VMware, Hyper-V, and Nutanix.
• Experience with vulnerability remediation using tools like Nessus.
• Strong AD, DNS, DHCP, and Group Policy administration.
• Excellent troubleshooting, analytical, and communication skills.

Responsibilities

• Install, configure, and maintain Microsoft Windows Server operating systems in classified environments.
• Manage virtualization platforms (VMware, Hyper-V, Nutanix) for availability and security.
• Administer enterprise services (Exchange, SQL Server, Jira, Confluence) and security tools.
• Troubleshoot hardware, software, networking, and infrastructure issues across networks.
• Monitor performance, apply patches, and implement security mitigations.
• Prepare SIA packages and coordinate approvals for changes.

Skills

Windows Server

VMware

Hyper-V

Nutanix

Active Directory

DNS

DHCP

Group Policy

Nessus

Security+

Education

Bachelor's degree or equivalent experience

Tools

VMware

Hyper-V

Nutanix

Nessus

Job description

Job Title: Classified Systems Administrator and ISSOJob Category: Information TechnologyTime Type: Full timeMinimum Clearance Required to Start: SecretEmployee Type: RegularPercentage of Travel Required: Up to 10%Type of Travel: Continental US* * *The OpportunityCACI is seeking a Classified Systems Administrator| ISSO to support and maintain mission-critical classified information systems in a secure environment. This role combines systems engineering, systems administration, cybersecurity, virtualization, and Information Assurance (IA) responsibilities to ensure the reliability, security, and compliance of classified networks. The ideal candidate will manage Windows Server infrastructure, virtualization platforms, enterprise applications, storage solutions, and security technologies while supporting DCSA/NISPOM compliance requirements. This position also provides technical leadership, mentors junior team members, and supports continuous system modernization in a high-security environment. An active Secret security clearance is required.ResponsibilitiesInstall, configure, administer, and maintain Microsoft Windows Server operating systems across classified environments.Manage virtualization platforms including VMware, Hyper-V, and Nutanix, ensuring availability, performance, and security.Administer enterprise services and applications including Microsoft Exchange, Microsoft SQL Server, Skype for Business, Jira, and Confluence.Troubleshoot, analyze, and resolve hardware, software, networking, and infrastructure issues across multiple classified networks.Monitor system performance, apply operating system patches, and implement security mitigations using vulnerability scanning tools such as Nessus.Manage enterprise storage platforms including Pure Storage, Dell PowerVault, and Synology appliances.Administer privileged access and security solutions including RSA and CyberArk.Process classified user account requests, access modifications, and Active Directory administration in accordance with DoD and NISPOM requirements.Conduct new user security briefings and ensure compliance with classified system Rules of Behavior.Serve as the onsite Data Transfer Agent (DTA), performing, documenting, and auditing authorized classified data transfers while maintaining removable media accountability.Maintain accurate inventory and accountability of classified IT assets, removable media, and peripheral equipment in accordance with DCSA requirements.Prepare and submit Security Impact Analysis (SIA) packages for hardware, software, and configuration changes, coordinating approvals prior to implementation.Provide Tier III technical support, mentor junior technicians, communicate escalation status to leadership, and participate in after-hours maintenance and outage support.Qualifications:RequiredBachelor's degree (or equivalent experience) with 7+ years of Systems Engineering and Systems Administration experience.Active Secret (TS) security clearance .CompTIA Security+ (or equivalent DoD-approved certification).Extensive experience administering Microsoft Windows Server environments, including installation, configuration, patch management, and performance optimization.Hands-on experience managing VMware, Hyper-V, and Nutanix virtualization environments.Experience implementing vulnerability remediation and security mitigations using enterprise security tools (e.g., Nessus).Strong knowledge of Microsoft Active Directory, DNS, DHCP, and Group Policy administration.Excellent troubleshooting, analytical, critical thinking, and problem-solving skills.Strong written and verbal communication skills with the ability to work independently and within cross-functional technical teams.Demonstrated commitment to continuous learning and supporting mission-critical classified environments.DesiredExperience administering Microsoft SQL Server.Experience supporting Skype for Business and Microsoft MECM/SCCM environments.Experience managing McAfee/Trellix endpoint security solutions.Experience with enterprise backup solutions such as Nakivo and Commvault.Experience supporting classified Information Assurance processes, Security Impact Analyses (SIAs), DCSA compliance, and secure data transfer operations.-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:$103,800 - $218,100CACI is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, age, national origin, disability, status as a protected veteran, or any other protected characteristic.