System Administrator - Multiple Openings

Si Tec Consulting; Lexington Park (MD); On-site; USD 75,000 - 140,000; Full time

Job summary

SITEC Consulting seeks System Administrators at Junior, Journey, and Senior levels to support a mission-focused government software hosting environment. The team will manage physical and virtual infrastructure, deploy servers and applications, and maintain secure configurations.

Ideal candidates have hands-on Windows/Linux administration, ACAS scanning experience, DISA STIGs, RMF compliance, and Active Directory expertise. U.S.

Qualifications

• Hands-on System Administration experience in Windows, Linux, or mixed operating-system environments.
• Experience with ACAS vulnerability scanning and credentialing.
• Experience implementing or maintaining DISA STIGs and supporting RMF compliance.
• Experience building, configuring, maintaining, or troubleshooting servers.
• Experience supporting virtualized infrastructure.
• Experience deploying and maintaining software applications.
• Working knowledge of networking and virtual networking concepts.
• Certifications: DoD 8570/8140 or Security+; OS certifications.
• U.S. Citizen with ability to obtain TS clearance.

Responsibilities

• Deploy, configure, administer, and maintain server infrastructure.
• Build and configure Windows and Linux servers for operational environments.
• Deploy and manage virtual machines using VMware, ESXi, and vSphere.
• Support virtual networking, storage, containers, and enterprise infrastructure technologies.
• Install, configure, deploy, maintain, and troubleshoot software applications.
• Perform system maintenance, patching, configuration changes, and vulnerability remediation.
• Conduct ACAS scanning, credentialed scans, vulnerability analysis, and remediation activities.
• Apply and maintain DISA STIGs and support RMF compliance requirements.
• Maintain the security and configuration posture of information systems through continuous monitoring and routine security activities.
• Configure and manage user accounts, permissions, groups, and access controls.
• Support Active Directory and related enterprise identity services.
• Maintain system backups and support disaster recovery and system restoration activities.
• Troubleshoot hardware, software, server, virtualization, networking, and application issues.
• Provide technical support and guidance to customers and internal teams.
• Maintain technical documentation, including system configurations, knowledge-base articles, incident response actions, and administrative procedures.
• Support networking requirements within on-premises infrastructure.
• Participate in technical planning and Agile project activities.

Skills

System administration

Windows admin

Linux admin

ACAS vulnerability scanning

DISA STIGs

RMF compliance

Active Directory

VMware

vSphere

ESXi

Networking basics

Credentialing

DoD 8570/8140

Secret clearance

U.S. Citizenship

Server builds & deployments

Application deployment

Tools

VMware

Nessus

ACAS

ESXi

vSphere

Windows Server

Red Hat Enterprise Linux

Active Directory

Job description

System Administrator - Junior / Journey / Senior

SITEC Consulting is seeking System Administrators to support a mission-focused government software hosting environment. We are looking for hands‑on administrators with experience supporting physical and virtual infrastructure, deploying servers and applications, maintaining secure system configurations, and troubleshooting complex technical issues.

Multiple experience levels are being considered, with a particular need for Journey-level System Administrators. Strong Junior and Senior candidates are also encouraged to apply.

Key Responsibilities

• Deploy, configure, administer, and maintain physical and virtual server infrastructure.
• Build and configure Windows and/or Linux servers for operational environments.
• Deploy and manage virtual machines using VMware, ESXi, and vSphere.
• Support virtual networking, storage, containers, and other enterprise infrastructure technologies.
• Install, configure, deploy, maintain, and troubleshoot software applications.
• Perform system maintenance, patching, configuration changes, and vulnerability remediation.
• Conduct ACAS scanning, credentialed scans, vulnerability analysis, and remediation activities.
• Apply and maintain DISA STIGs and support Risk Management Framework (RMF) compliance requirements.
• Maintain the security and configuration posture of information systems through continuous monitoring and routine security activities.
• Configure and manage user accounts, permissions, groups, and access controls.
• Support Active Directory and related enterprise identity services.
• Maintain system backups and support disaster recovery and system restoration activities.
• Troubleshoot hardware, software, server, virtualization, networking, and application issues.
• Provide technical support and guidance to customers and internal teams.
• Maintain technical documentation, including system configurations, knowledge-base articles, incident response actions, and administrative procedures.
• Support networking requirements within on-premises infrastructure.
• Participate in technical planning and Agile project activities.

Required Qualifications

• Hands-on System Administration experience in Windows, Linux, or mixed operating-system environments.
• Experience with ACAS vulnerability scanning and credentialing.
• Experience implementing or maintaining DISA STIGs and supporting RMF compliance.
• Experience building, configuring, maintaining, or troubleshooting servers.
• Experience supporting virtualized infrastructure.
• Experience deploying and maintaining software applications.
• Working knowledge of networking and virtual networking concepts.
• Familiarity with Linux operating systems.
• CompTIA Security+ or another applicable DoD 8570/8140 certification.
• Current Windows or Linux Operating System certification.
• Active Secret clearance with the ability to obtain Top Secret; Interim Top Secret required to start.
• Must be a U.S. Citizen.

Preferred Technical Experience

Experience with one or more of the following is highly desired:

• VMware / vSphere / ESXi
• ACAS / Nessus
• Windows Server
• Red Hat Enterprise Linux (RHEL)
• Server builds and deployments
• Application deployment and sustainment
• Virtual networking
• Active Directory
• System backups and recovery
• Containers
• Cisco networking
• SAN / enterprise storage
• DISA STIG implementation
• RMF / cybersecurity compliance

Experience Levels

Junior System Administrator

• Minimum of 1 year of relevant System Administration experience.

Journey System Administrator

• Minimum of 5 years of relevant System Administration experience.

Senior System Administrator

• Minimum of 10 years of relevant System Administration experience.

Candidates do not need to meet every preferred skill listed above to be considered. We are particularly interested in candidates with strong hands‑on experience in VMware administration, server builds, ACAS scanning, application deployments, and Windows/Linux system administration.