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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Systems Administrator - **Company:** Crossfield Technology Llc - **Location:** Philadelphia, PA, United States - **Experience:** Expert - **Salary:** $95,000.0 - $105,000.0 - **Contract:** Permanent contract - **Skills:** Microsoft Windows, Active Directory, Amazon Web Services, Audit Trail, Microsoft Azure, Bash Shell, Cloud Computing, Configuration Management, System Configuration, Dynamic Host Configuration Protocol, Linux, Domain Name System (DNS), Multi-Factor Authentication, Hyper-V, IT Management, IP Address Management, Subnetting, Virtual Private Networks (VPN), Job Scheduling, Linux System Administration, Windows Servers, Network Diagrams, Network Virtualization, Package Management Systems, Paessler Router Traffic Grapher, PCI Data Security Standards, Windows PowerShell, Ansible, Microsoft SharePoint, TCP/IP, Virtual Local Area Networks, Virtual Machines, Virtualization Technology, VMware VSphere, Zabbix, Datadog, Data Storage Management, Cloud Platform System, Computer Network Technologies, Containerization, Kubernetes, Patch Management, Firewall Services Module, Terraform, Docker - **Published:** October 20, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=a00337ceaa749e70 ## About the Role * Five or more years of professional systems administration experience in production environments * Advanced Windows Server and Active Directory administration, including Group Policy design and PowerShell automation * Production virtualization experience with VMware vSphere or Microsoft Hyper-V * Cloud infrastructure experience with AWS or Azure, including virtual networking, compute, identity, and storage services * Working networking knowledge: TCP/IP, subnetting, DNS, DHCP, VLANs, VPN concentrators, and stateful firewall rule administration * Demonstrable backup and recovery experience, including performed and validated restores * Experience with monitoring and alerting platforms in an operational role * Strong written communication; this position requires documentation to an audit standard * Willingness to work on-site in Philadelphia and participate in the assigned on-call rotation, * Microsoft certification (AZ-104, AZ-800/801) or equivalent demonstrated cloud competency * Linux system administration beyond foundational level * Configuration management or infrastructure-as-code experience (Ansible, Terraform) * Experience operating hybrid identity environments integrating on-premises Active Directory with Entra ID * Prior work in regulated environments requiring evidence of change control and access review * Familiarity with container platforms (Docker, Kubernetes) in a support capacity ## Description As a Systems Administrator, You will be responsible for the deployment, configuration, security, and ongoing operation of the organization's server, storage, virtualization, and identity infrastructure. The position performs hands-on administration across on-premises and cloud environments, responds to production incidents under defined escalation procedures, and maintains the documentation and standards required for auditable, repeatable operations. Reporting to IT leadership, this role functions as the technical owner of core infrastructure services., Infrastructure Administration * Administer Windows Server environments (2016 or later), including role configuration, storage management, and server hardening against established baselines * Administer Linux systems supporting internal services, including package management, service configuration, and log review * Manage Microsoft Active Directory: user and computer objects, organizational unit structure, Group Policy Objects, and delegation models * Administer Microsoft 365 tenant services, including Exchange Online, SharePoint, and Entra ID sign-in, conditional access, and multi-factor authentication policies * Operate virtualization platforms (VMware vSphere or Microsoft Hyper-V): virtual machine provisioning, resource allocation, snapshot management, and host patching * Maintain DNS, DHCP, and IP address management functions for internal networks * Administer enterprise backup infrastructure, including job scheduling, retention policy enforcement, and documented restore testing at defined intervals Monitoring, Incident Response, and Maintenance * Monitor infrastructure using the organization's alerting platform (Zabbix, PRTG, Datadog, or equivalent); investigate and resolve alerts within established response targets * Perform root-cause analysis for production incidents and produce written incident reports documenting cause, impact, and corrective action * Execute patch management for server and workstation operating systems and third-party software according to the monthly maintenance schedule * Conduct planned maintenance and infrastructure changes during approved change windows, following change-management procedures and rollback planning * Participate in the on-call rotation, including after-hours response to production incidents Security and Compliance * Implement least-privilege access controls, including privileged account management and role-based access review * Maintain endpoint protection, host firewall rules, and audit logging in accordance with organizational security standards * Support compliance requirements (HIPAA, SOC 2, or PCI-DSS, as applicable) through evidence collection, access audits, and configuration documentation Documentation and Project Work * Maintain infrastructure documentation: system inventories, configuration records, network diagrams, and operational runbooks * Execute infrastructure projects - migrations, capacity expansions, and tool evaluations, from requirements through implementation and handover * Automate recurring operational tasks in PowerShell or Bash, with version-controlled scripts