Windows / Linux System Administrator with Security Clearance

Windows / Linux Systems Administrator - Telephony Infrastructure Location: Annapolis Junction, MD Schedule: Full-time | Onsite Clearance: Active Secret clearance required Salary Range: $90,000-$100,000 annually The Opportunity We are hiring an experienced Windows / Linux Systems Administrator to support internal enterprise telephony systems for a Homeland Security mission. This role combines systems administration, telephony, virtualization, networking, and security. You'll provide hands-on technical expertise across Windows and Linux servers while supporting the infrastructure behind critical voice and call-management services. This position is onsite in Annapolis Junction, Maryland and supports systems requiring 24x7x365 availability.

What You'll Do

• Manage and support enterprise telephony environments, including hardware, software, peripherals, and applications such as WFO/WFM, CMS, and call recording platforms.
• Install, configure, operate, monitor, and maintain enterprise infrastructure, including IIS web servers, application servers, telecom hardware, Dell PowerEdge servers, and Avaya J Series phones.
• Troubleshoot and resolve issues involving telephony platforms, Windows and Linux servers, network connectivity, and system integrations.
• Support integrations with Active Directory, DNS, DHCP, and LDAP.
• Work across technical teams to implement telephony solutions supporting high availability, call quality, security, and performance requirements.
• Apply scheduled and emergency patches to Windows and Linux Server environments to maintain security and compliance.
• Plan, test, and execute system upgrades and migrations.
• Conduct system health checks and preventive maintenance.
• Coordinate with security teams to address audit findings and implement appropriate remediation.
• Perform other assigned responsibilities as needed. What You'll Bring
• An active Secret security clearance.
• U.S. citizenship. Due to contract requirements, candidates with dual citizenship cannot be considered.
• 7+ years of relevant experience in systems administration or systems engineering.
• Experience administering Windows and Linux Server environments, including installation, patching, troubleshooting, and ongoing support.
• Experience with telephony platforms, including Avaya and call recording/workforce management applications.
• Experience with VMware environments, including ESXi and vCenter, covering installation, upgrades, troubleshooting, and ESXi certificate management.
• Networking experience involving IPv4/IPv6, ports and protocols, and monitoring.
• Familiarity with the remediation and validation of security vulnerabilities in Windows and Linux Server environments.
• Proficiency managing and monitoring infrastructure, including telephony peripherals and server systems.
• Knowledge of client/server certificate management.
• Experience with Active Directory and Group Policy Administration.
• Ability to reside within a commutable distance of Annapolis Junction, MD for daily onsite work and on-call responsibilities.
• Willingness and ability to meet recall requirements for systems requiring 24x7x365 uptime, including participation in a rotational on-call schedule.

Preferred Qualifications

• Prior DHS suitability.
• Scripting experience with PowerShell and/or Shell scripting.
• Experience with VMware virtualization technologies.
• Experience with Microsoft SQL Server and PostgreSQL databases.
• Demonstrated experience administering Active Directory and Group Policy.
• Experience with security vulnerability remediation and validation. Compensation The annual salary range for this position is $90,000-$100,000.