Senior Systems Administrator

Essential Duties & Responsibilities: - Installs, configures, administers, maintains, and decommissions physical and virtual Windows and Linux servers within the Hill CEDC environment. - Performs operating system installation, configuration, patching, hardening, upgrades, and lifecycle maintenance in accordance with approved security and change-management processes. - Administers virtualized environments, including creating, configuring, monitoring, migrating, and retiring virtual machines and associated resources. - Diagnoses and resolves system, operating system, application, virtualization, storage, network-connectivity, and performance issues to maximize availability and operational service levels. - Coordinates with hardware, network, cybersecurity, database, storage, and application-support personnel to troubleshoot and resolve infrastructure incidents and service requests. - Configures and maintains Windows- and Linux-based services, including user authentication, directory services, domain services, DNS, DHCP, file services, print services, and system logging, as applicable. - Performs system backups, restores, replication, and recovery actions; supports validation of backup and disaster-recovery procedures. - Monitors server health, system performance, capacity, availability, event logs, and security alerts; takes corrective action or escalates issues as required. - Implements and maintains approved operating system security configurations, vulnerability remediation actions, security patches, antivirus or endpoint-security tools, and compliance settings. - Supports assessment and remediation of cybersecurity vulnerabilities, misconfigurations, and findings in coordination with cybersecurity personnel and system owners. - Maintains privileged-access controls, account administration, group memberships, and role-based access in accordance with approved procedures and least-privilege principles. - Supports installation, configuration, and sustainment of enterprise applications and supporting middleware in coordination with application owners and vendors. - Performs software installation, licensing support, version upgrades, and configuration changes while maintaining accurate system documentation. - Develops, maintains, and executes standard operating procedures (SOPs), system-administration guides, configuration baselines, and troubleshooting documentation. - Documents system configurations, dependencies, maintenance actions, incidents, changes, and recovery procedures under configuration-management control. - Develops and maintains system configuration baselines consistent with the 75 ABW/SC configuration-management plan. - Supports equipment inventory, software-license tracking, capacity management, rightsizing, and lifecycle management of server and virtual infrastructure resources. - Supports End-of-Life/End-of-Support (EOL/EOS) planning, technology refresh efforts, migration planning, and market research for replacement software and infrastructure commodities. - Participates in approved change-management, maintenance-window, outage-notification, and service-restoration processes. - Supports Portable Operating Data Center (POD) systems, including installation, configuration, monitoring, maintenance, and upgrades; supports short-notice travel to remote sit es as required. - Provides technical leadership, mentoring, and cross-training to junior system administrators and other engineering personnel. - Ensures system designs and configurations adequately address Department of Defense and Air Force cybersecurity requirements. - Performs other related duties as assigned. Education, Certification & Experience Requirements: Education: - Bachelor's degree in Information Technology, Computer Science, Cybersecurity, Business, or a related field; equivalent relevant professional e perience may be considered. - 8+ years of progressively responsible system-administration experience**, including experience supporting enterprise Windows and Linux server environments. Certifications: - Active Secret Clearance (or ability to obtain/maintain) - CompTIA Sec+ CE (Required) - CompTIA Server+ (Preferred) - CompTIA Linux+ (Preferred) - Microsoft Windows Server or Azure administration certification (Preferred) - Red Hat Certified System Administrator (RHCSA) or comparable Linux certification (Preferred) - VMware Certified Professional (VCP) or comparable virtualization certification (Preferred) - ITIL Foundation (Preferred) Knowledge, Skills & Abilities: - Demonstrated experience administering and troubleshooting Windows Server and Linux operating systems in an enterprise or data-center environment. - Experience supporting physical servers, virtual machines, hypervisors, and enterprise virtualization platforms. - Knowledge of Active Directory, Group Policy, DNS, DHCP, authentication services, file services, and access-control administration. - Knowledge of system patching, vulnerability remediation, endpoint security, operating-system hardening, and security compliance requirements. - Experience with system monitoring, log analysis, performance tuning, capacity management, and incident response. - Knowledge of backup, restore, replication, and disaster-recovery concepts and procedures. - Experience using configuration-management, ticketing, asset-management, and change-management processes. - Ability to develop and maintain technical documentation, SOPs, diagrams, configuration baselines, and system-administration records. - Ability to work independently, prioritize multiple tasks, communicate technical issues clearly, and coordinate effectively with government personnel, vendors, and contractor teams. &nb sp; - Ability to mentor, train, and cross-train other engineers and system administrators. - Ability to support occasional temporary changes to work schedules and short-notice travel requirements. Command Cyber Solutions, LLC is an equal opportunity employer. Command Cyber solutions, LLC does not discriminate in employment opportunities or practices on the basis of race, color, religion, sex, national origin, age, disability, marital status or any other characteristic protected by law.