As a Systems Engineer at The One 23 Group, your day-to-day responsibilities will vary based on your specialization and seniority, but will generally center around the following core activities:

• System Deployment and Maintenance: You will provision, configure, and maintain physical and virtual servers running RHEL or Windows Server in both on-premises and cloud environments. This includes executing routine system upgrades, kernel updates, and software installations.
• Infrastructure Hardening and Compliance: You will be responsible for implementing robust security controls, aligning systems with DISA STIG requirements, remediating vulnerability scan findings, and supporting continuous monitoring and compliance audits.
• Automation and Orchestration: You will actively develop and maintain automation scripts and configuration management code to streamline provisioning, patching, backup verification, and monitoring processes.
• Performance Optimization and Monitoring: You will monitor system performance, capacity, and availability, proactively identifying potential bottlenecks and tuning system parameters to ensure optimal resource utilization.
• Tier 3 Technical Support: You will serve as an escalation point for complex technical issues, collaborating with help desk specialists, network engineers, and software developers to resolve high-priority system outages and performance degradation.
• Technical Leadership and Documentation: Senior and Team Lead roles will actively mentor junior administrators, establish engineering standards, and maintain comprehensive, up-to-date documentation of system architectures, standard operating procedures (SOPs), and configuration baselines.

To be competitive for a Systems Engineer position at The One 23 Group, candidates should possess a strong blend of technical expertise, security credentials, and collaborative skills.

Technical Skills & Certifications

• Operating Systems: Strong hands-on experience with Red Hat Enterprise Linux (RHEL) (versions 7, 8, or 9) or Windows Server (2016, 2019, 2022).
• Automation: Proficiency with configuration management tools, particularly Ansible, and scripting languages such as Bash, PowerShell, or Python.
• Security Compliance: Familiarity with federal security frameworks, including NIST SP 800-53, DISA STIGs, and vulnerability management tools (e.g., Nessus, ACAS).
• Core Certifications: CompTIA Security+ CE (or equivalent DoD 8577.01-M IAT Level II certification) is highly preferred and often mandatory for our Arlington, VA roles. Red Hat Certified System Administrator (RHCSA) or Microsoft Certified: Windows Server Hybrid Administrator Associate is a major plus.

Experience & Background

• Red Hat Linux Engineer (Senior): Typically requires 8+ years of experience managing enterprise Linux environments, designing high-availability architectures, and leading automation initiatives.
• Red Hat Linux Engineer (Journeyman): Typically requires 3-6 years of systems administration experience, with a solid grasp of Linux fundamentals and basic scripting.
• Windows SysAdmin Team Lead: Requires 6+ years of Windows administration experience, with proven experience leading technical teams, managing Active Directory, and coordinating complex projects.
• Systems Administrator / Help Desk Specialist: Requires 1-4 years of experience diagnosing hardware, software, and network issues, with a strong customer-service mindset and basic OS administration skills.

Q: How technical are the interviews at The One 23 Group? A: They are highly technical and practical. Rather than asking abstract trivia questions, our interviewers will present you with real-world scenarios—such as a failing server, a broken automation script, or a security audit finding—and ask you to walk through your diagnostic and remediation process.

Q: What is the typical timeline for the hiring process? A: The process generally takes between two to four weeks from the initial recruiter screen to a formal offer. This timeline can vary depending on candidate availability, technical panel scheduling, and any contract-specific security clearance verifications.

Q: Are these roles remote, hybrid, or on-site? A: Due to the secure nature of the systems we manage and our close collaboration with clients, most of our Systems Engineer positions located in Arlington, VA operate on a hybrid or fully on-site schedule. Specific flexibility is discussed during the initial recruiter screen.

Q: What differentiates a successful candidate from an unsuccessful one? A: Successful candidates demonstrate a deep curiosity about how systems work under the hood, a strong commitment to security best practices, and an "automate-first" mindset. They communicate clearly, explain their troubleshooting steps logically, and are comfortable admitting what they do not know while explaining how they would find the answer.

• Brush up on networking fundamentals: Systems do not exist in a vacuum. You should understand DNS resolution, routing, subnets, firewalls, and how to use tools like tcpdump, wireshark, or nslookup to diagnose network-related system issues.
• Be ready to talk about security: No matter the role, expect questions on how you secure your systems. Understand the difference between symmetric and asymmetric encryption, how to manage firewalls (e.g., firewalld, Windows Firewall), and how to enforce access controls.
• Structure your behavioral answers using the STAR method: When asked about past experiences, clearly define the Situation, the Task at hand, the Action you personally took, and the Result of your efforts. Focus on quantitative outcomes whenever possible (e.g., "reduced deployment time by 40%").
• Highlight your leadership and mentorship: If you are interviewing for a senior or team lead role, emphasize how you help others grow. Share examples of documentation you have written, junior engineers you have mentored, or processes you standardise across teams.

The Systems Engineer role at The One 23 Group is a fantastic opportunity for technical professionals who want to work on critical infrastructure, solve complex scaling challenges, and make a tangible impact in secure enterprise environments. Whether you are managing cutting-edge Red Hat Linux deployments, leading a high-performing Windows Systems team, or securing environments in Arlington, VA, you will find a culture that values technical excellence, continuous learning, and collaborative problem-solving.

To maximize your chances of success, focus your preparation on the core operating system concepts, practice explaining your troubleshooting methodologies out loud, and ensure you can discuss automation and security hardening in detail.

Explore additional community-reported interview experiences, salary insights, and preparation resources on Dataford to help you feel fully prepared and confident heading into your conversations with the hiring team.

The salary ranges listed above reflect the diverse levels of seniority and specialization within our systems engineering team, spanning from entry-level support specialists to highly specialized senior Linux engineers. When evaluating an offer, consider that The One 23 Group structures compensation packages to reflect technical expertise, certifications, and the specific security clearances required for our mission-critical programs. Focused preparation on the core technical and security domains highlighted in this guide is your best path to securing a highly competitive offer.