System Administrator 3
$104.24k - $130.3kM.C. Dean
Overview About M.C. Dean M.C. Dean is Building Intelligence. We design, build, operate, and maintain cyber-physical solutions for the nation's most mission-critical facilities, secure environments, complex infrastructure, and global enterprises. With over 9,000 employees, our capabilities span electrical, electronic security, telecommunications, life safety, automation and controls, audiovisual, and IT systems. Headquarters in Tysons, Virginia, M.C. Dean delivers resilient, secure, and innovative power and technology solutions through engineering expertise and smart systems integration. Why Join Us? Our people are passionate about engineering innovation that improves lives and drives impactful change. Guided by our core values-agility, expertise, and trust-we foster a collaborative and forward-thinking work environment. At M.C. Dean, we are committed to building the next generation of technical leaders in electrical, engineering, and cybersecurity industries. Responsibilities What you'll do: In this role, you will serve as a senior systems administrator and technical lead for secure Operational Technology (OT) and Industrial Control System (ICS) infrastructure. You will own the solution lifecycle from bidding and design through implementation, cybersecurity hardening, testing, commissioning, documentation, and customer handoff, while coordinating with estimating, engineering, cybersecurity, network, controls, project management, vendors, field teams, and customers. Main responsibilities include but are not limited to: Support capture, bidding, and change-order development by defining technical approaches; preparing basis-of-estimate inputs, labor and material requirements, proposal narratives, assumptions, risks, and clarifications; and evaluating vendor solutions and quotations. Serve as the technical lead and primary customer-facing point of contact; lead requirements discovery and design coordination with project stakeholders; establish availability, performance, cybersecurity, maintainability, and lifecycle objectives; communicate tradeoffs; resolve comments; and document technical decisions. Develop and maintain design packages, including narratives, system architecture and block diagrams, logical and physical network diagrams, virtualization and storage designs, backup and recovery architectures, rack elevations, equipment schedules, bills of material, interface documents, and as-built drawings. Architect, deploy, configure, and administer highly available VMware vSphere/ESXi and Microsoft Hyper-V environments, including clusters, hosts, virtual networking, resource allocation, failover, monitoring, patching, and lifecycle management. Design, build, secure, and maintain Windows Server platforms and core services, including Active Directory, Group Policy, DNS, DHCP, certificate services, time synchronization, file services, service accounts, permissions, and role-based access controls. Design and administer enterprise backup, replication, storage, and disaster recovery solutions across SAN, NAS, and direct-attached platforms; configure RAID, volumes, LUNs, snapshots, replication, capacity, recovery objectives, and validated restore procedures. Install, integrate, and maintain OT/ICS applications and supporting infrastructure, including highly available SQL services, virtual desktop infrastructure, monitoring, logging, endpoint protection, and third-party vendor applications. Coordinate secure OT/ICS network implementation, including segmentation, VLANs, routing, firewalls, industrial demilitarized zones, jump hosts, controlled remote access, secure management paths, and resilient network services. Harden servers, workstations, hypervisors, databases, applications, and supporting devices using applicable STIGs and secure baselines; lead patching, vulnerability remediation, configuration management, and change control for connected, disconnected, air-gapped, classified, and mission-critical environments. Support RMF and cybersecurity authorization activities by producing control implementation details, configuration records, vulnerability remediation plans, test results, and other required technical evidence. Review submittals, procurement packages, software licensing, support agreements, and equipment selections for compatibility, compliance, cybersecurity, maintainability, and alignment with the approved design. Lead system staging, integration, FAT/SAT, backup and restore testing, failover testing, performance verification, field startup, commissioning, cutover, and complex troubleshooting; perform root cause analysis and drive issues to closure. Manage technical risks, interfaces, design changes, requests for information, configuration baselines, and project status while providing technical direction and mentoring to administrators, engineers, subcontractors, vendors, and field personnel. Produce complete SOPs, installation and configuration guides, test plans and reports, maintenance and recovery procedures, cybersecurity checklists, operations and maintenance manuals, and final as-built packages; lead customer demonstrations, training, acceptance, turnover, and transition to support. Qualifications Clearance/Citizen Type : Applicants selected will be subject to a government security investigation and must meet eligibility requirements, including U.S. citizenship, for access to classified information. The ability to obtain and maintain a U.S. Top Secret security clearance is required. Key Requirements Education Bachelor's Degree and 5+ years of progressive experience; or Associate's Degree and 8+ years of progressive experience; or High School Diploma or equivalent and 10+ years of progressive experience. Progressive systems administration or systems engineering experience designing, implementing, securing, commissioning, and sustaining enterprise or OT/ICS computing environments through the complete project lifecycle. Advanced hands-on experience with VMware vSphere/ESXi and/or Microsoft Hyper-V, Windows Server, Active Directory, Group Policy, DNS, DHCP, authentication, permissions, and secure configuration management. Demonstrated experience with enterprise backup and recovery platforms and storage arrays, including redundancy, replication, restore validation, capacity planning, and disaster recovery. Demonstrated knowledge of STIG implementation, Windows patching, vulnerability remediation, endpoint protection, security logging, and RMF or comparable cybersecurity compliance processes. Working knowledge of OT/ICS network architecture and TCP/IP, VLANs, routing, firewalls, segmentation, redundancy, remote access, and network troubleshooting. Ability to develop and review technical designs, diagrams, bills of material, estimates, test procedures, as-built documentation, and operations and maintenance deliverables. Strong customer-facing communication and technical leadership skills, with experience coordinating multidisciplinary teams, vendors, subcontractors, and field personnel while managing multiple priorities with minimal supervision. Proficiency with Microsoft Word, Excel, Visio, and PowerPoint. An active CompTIA Security+ or approved higher-level certification such as CASP+ or CISSP is required. Reliable attendance at customer sites and the ability to work flexible shifts, including nights, weekends, and holidays, when required for testing, cutover, or commissioning. Preferred Experience Experience with ACAS or Tenable, HBSS or enterprise endpoint security, SRR tools, eMASS, DoD RMF, NIST SP 800-53, NIST SP 800-82, ISA/IEC 62443, UFC 4-010-06, and related OT/ICS cybersecurity guidance. Experience with Veeam, Commvault, Rubrik, Dell, NetApp, HPE, or comparable backup and storage technologies; highly available SQL, Citrix or other VDI platforms, centralized monitoring and logging, PowerShell, and secure or air-gapped environments. Experience supporting Physical Access Control Systems, industrial control applications, integrated security systems, or other mission-critical OT platforms, including FAT/SAT, commissioning, customer training, and turnover. Travel Up to 30% annually to CONUS and OCONUS locations. Abilities Exposure to computer screens for an extended period of time. Sitting for extended periods of time. Reach by extending hands or arms in any direction. Have finger dexterity in order to manipulate objects with fingers rather than whole hands or arms, for example, using a keyboard. Listen to and understand information and ideas presented through spoken words and sentences. Communicate information and ideas in speaking so others will understand. Read and understand information and ideas presented in writing. Apply general rules to specific problems to produce answers that make sense. Identify and understand the speech of another person. Pay Range USD $104,240.00 - USD $130,300.00 /Yr. #J-18808-Ljbffr M.C. Dean
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