Senior Principal Linux\Windows System Administrator

• Administer and maintain Red Hat Enterprise Linux & Windows servers and workstations in a mission-critical environment.
• Work with the Security and IT teams to develop and implement a plan to deploy RHEL workstations and servers within the CMMC framework for use in our enterprise environment.
• Administer and maintain Microsoft Azure and Office 365 services.
• Manage all aspects of Windows Active Directory infrastructure including Domain Controllers, DNS servers, DHCP servers, and file servers.
• Configure and manage HPC (High Performance Computing) Linux clusters.
• Installation, configuration, and support of servers, enterprise storage and associated equipment, network and direct attached storage systems and associated equipment.
• Integrate Linux systems with Microsoft Active Directory for authentication and policy management.
• Implement and maintain security best practices, including system hardening, patch management, and compliance with security frameworks (e.g., DISA STIGs, CMMC, CIS benchmarks).
• Troubleshoot and resolve complex issues related to Linux and Windows interoperability.
• Automate administrative tasks using scripting languages (e.g., Bash, Python, Ansible).
• Collaborate with security teams to ensure systems meet cybersecurity requirements.
• Track and maintain computer assets using asset management tools and ensure asset management systems have up-to-date information.
• Monitor system performance and implement proactive measures for optimization and reliability.
• Provide analysis related to the design, development, and implementation of hardware and software solutions.
• Document system deployments and configurations.
• Research and/or contact vendors regarding technical problems and solutions.
• Demonstrate professionalism in response to customer requests.

• 14+ years of total System Administration experience
• 7+ years of experience in Linux system administration
• 5+ years managing Red Hat Enterprise Linux in Microsoft Windows/ Azure enterprise environments.
• Proven experience integrating Linux systems with Microsoft Active Directory (SSSD, Kerberos, LDAP, Intune).
• Strong knowledge of security hardening and compliance standards.
• Proficiency in shell scripting and automation tools (Ansible preferred).
• Familiarity with virtualization and cloud technologies (Azure preferred).
• Excellent troubleshooting and problem-solving skills.

• BS or equivalent degree in Computer Science or related field.

• Red Hat Certified Engineer (RHCE) or equivalent certification.
• Windows Server Hybrid Administrator Associate or similar Microsoft 365 certifications.
• Experience in DoD or other regulated environments with strict security requirements.
• Knowledge of SELinux, firewalld, fapolicyd, and secure networking practices.
• Experience managing GCC High Microsoft Azure/ Office 365.
• Experience configuring & managing Bright High Performance Computing clusters.

• Must have the ability to obtain/maintain a US government security clearance.
• US citizenship is required.

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  Interesting Work:
  
  
  
  Our co-workers support some of the most important and critical programs to our national defense and security.
  
  
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  Values:
  
  
  
  Our first core value is that employees come first. We challenge our co-workers to provide the highest level of support and service, and reward them with some of the best benefits in the industry.
  
  
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  100% Employee Owned:
  
  
  
  We have a stake in each other's success, and the success of our customers. It's also nice to know what's going on across the company; we have company wide town-hall meetings three times a year.
  
  
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  Great Benefits - Most Full-Time Staff Are Eligible for:
  
  
  




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  Starting PTO accrual of 20 days PTO/year + 10 holidays/year
  
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  Flexible schedules
  
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  6% 401k match with immediate vesting up to $9k annually
  
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  Semi-annual bonus eligibility (July and December)
  
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  Company funded Employee Stock Ownership Plan (ESOP) - a separate qualified retirement account
  
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  Up to $10,000 in annual educational reimbursement
  
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  Other company funded benefits, like life and disability insurance
  
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  Optional zero deductible Blue Cross/Blue Shield health insurance plan
  




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  Track Record of Success:
  
  
  
  We have grown every year since our founding in 1993.
  
  

Modern Technology Solutions, Inc. (MTSI) is a 100% employee-owned engineering services and solutions company that provides high-demand technical expertise in Digital Transformation, Modeling and Simulation, Rapid Capability Development, Test and Evaluation, Artificial Intelligence, Autonomy, Cybersecurity and Mission Assurance

MTSI delivers capabilities to solve problems of global importance. Founded in 1993, MTSI today has employees at over 20 offices and field sites worldwide.

For more information about MTSI, please visit www.mtsi-va.com