Classified Systems Administrator and ISSO Security Clearance

Position: Classified Systems Administrator and ISSO with Security Clearance
Job Title:

Classified Systems Administrator and ISSO Job Category:
Information Technology Time Type:
Full time Minimum Clearance Required to Start: TS/SCI with Polygraph Employee Type:
Regular Percentage of

Travel Required:

Up to 10% Type of Travel:
Continental US *
* * The Opportunity CACI 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 Top Secret security clearance with the ability to obtain a CI Polygraph is required. Responsibilities
* Install, 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 Power Vault, and Synology appliances.

* Administer privileged access and security solutions including RSA and Cyber Ark.

* 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:

Required
* Bachelor's degree (or equivalent experience) with 7+ years of Systems Engineering and Systems Administration experience.

* Active Top Secret (TS) security clearance with the ability to obtain a Counterintelligence (CI) Polygraph.

* 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. Desired
* Experience 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…