Senior System Administrator

Si Tec Consulting; Corridor North (MD); On-site; USD 110,000 - 150,000; Full time

Job summary

Si Tec Consulting is seeking a Senior Systems Administrator to ensure operational support for systems across hybrid environments. The ideal candidate will possess strong experience in Windows and Linux administration, patching, and support in a DoD environment.

The position requires an active TS/SCI with Polygraph and extensive experience, along with capabilities in automation and supporting mission-critical systems.

Qualifications

• 15 years of Systems Administration experience in similar programs.
• Active TS/SCI with Polygraph required.
• DoD 8570 compliance with IAT Level I.
• Strong knowledge in IAVA patching and reporting.

Responsibilities

• Administer and maintain Windows Server and Linux environments.
• Perform patching, troubleshooting, and operational support.
• Implement automation and manage AWS infrastructure.

Skills

Windows Server Administration

Linux Systems Administration

Vulnerability Remediation

Automation Scripting

Cloud Computing (AWS)

Problem-solving skills

Education

Bachelor's degree in a technical discipline

Tools

PowerShell

Bash

Python

Ansible

Terraform

AWS services (EC2, Lambda, CloudFormation, IAM)

Job description

SITEC is seeking a Senior Systems Administrator to support lifecycle sustainment activities for commercial and custom-developed education, learning, and training applications. This role will join an existing technical team responsible for maintaining secure, reliable, and high-performing IT systems across hybrid on-premises and cloud-based environments.

The ideal candidate is a self-motivated Systems Administrator with strong Windows and Linux experience, hands-on patching and vulnerability remediation knowledge, and the ability to support mission-critical systems in a fast-paced DoD environment.

Responsibilities

The Senior Systems Administrator will provide operational support, maintenance, troubleshooting, patching, automation, and system administration across enterprise Windows, Linux, and cloud-hosted environments. This position will support system reliability, security compliance, infrastructure modernization, and lifecycle sustainment activities.

Key Duties

• Administer and maintain Windows Server and Linux server environments.
• Perform IAVA patching, vulnerability remediation, and compliance reporting across enterprise systems.
• Provide troubleshooting, maintenance, and operational support for on-premises and cloud-hosted IT environments.
• Execute system patching, software maintenance, upgrades, hardening, and disk management.
• Implement and manage Windows Group Policy Objects and Active Directory-related administration.
• Develop automation scripts using PowerShell, Bash, Python, or related scripting languages.
• Support AWS cloud infrastructure using services such as EC2, Lambda, CloudFormation, and IAM.
• Assist with infrastructure as code initiatives using Ansible and Terraform.
• Develop and maintain system automation tools to improve reliability, efficiency, and uptime.
• Work collaboratively with technical teams in a fast-paced, mission-focused environment.

Required Qualifications

• Active TS/SCI with Polygraph.
• 15 years of Systems Administration experience supporting programs of similar scope, type, and complexity.
• Bachelor's degree in a technical discipline; 5 additional years of SA experience may be substituted in lieu of a degree.
• DoD 8570 compliance with IAT Level I.
• Experience maintaining Windows Server environments, including hardening, patching, upgrades, and disk management.
• Experience administering Linux servers, including patching and software maintenance.
• Experience with IAVA patching and reporting.
• Experience maintaining and upgrading installed software across enterprise systems.
• Strong troubleshooting and problem-solving skills across computer systems and software.

Desired Skills

• Strong hybrid Linux/Windows Systems Administration background.
• Hands-on experience with AWS services such as EC2, Lambda, CloudFormation, and IAM.
• Experience with automation and scripting tools including Ansible, Terraform, PowerShell, Bash, and Python.
• Experience with Active Directory and Group Policy Management.
• Understanding of cloud security practices, patch management, and compliance reporting.
• Ability to work independently and collaboratively in a fast-paced technical environment.

About SITEC

SITEC is an employee- and customer-focused Information Technology and Professional Services firm specializing in cybersecurity, software and systems engineering, systems administration, and lifecycle support services. We design, develop, and deliver mission-focused technology solutions that support the continuous operation and modernization of critical customer platforms.