Senior Systems Administrator - IT

Responsibilities

• Administer on-prem Active Directory: domain controllers, replication health, FSMO roles, Sites & Services, DNS, and Group Policy (design, testing, and staged fleet rollout).
• Manage hybrid identity: Entra Connect sync, ADFS, hybrid Azure AD join, and troubleshooting (e.g., PRT acquisition, device state).
• Administer Microsoft 365 / Entra ID: user lifecycle, licensing, Conditional Access, MFA enforcement, and Privileged Identity Management (PIM).
• Maintain service-account hygiene, privileged-group reviews, and least-privilege access.
• Drive security hardening initiatives. Remediate penetration-test findings and apply security baselines.
• Manage Windows Firewall policy centrally via GPO; maintain internal PKI/certificate lifecycle.
• Maintain audit trails and operator attribution for sensitive actions.
• Manage the Hyper-V virtualization fleet, server lifecycle, and storage.
• Administer multi-site network infrastructure: Fortigate VPN tunnels, UniFi wireless/switching, DHCP/DNS.
• Plan and deploy Windows Updates fleet-wide; monitor and orchestration.
• Own backup and disaster recovery: validate jobs, manage retention, and test restores.
• Operate and tune the Graylog SIEM and event-log pipeline; triage alerts across security platforms.
• Develop and maintain PowerShell automation.
• Maintain and extend internal operations tooling (custom dashboard, scheduled/automated reporting).
• Use Azure DevOps for source control, CI/CD pipelines, work tracking, and documentation.
• Maintain operational runbooks, change logs, and a knowledge-base wiki.
• Follow a methodical, change-managed approach for high-risk changes (audit → stage → validate).
• Support escalation support for endpoint, identity, email, and access issues; partner with help-desk operations on SLA-tracked tickets.

Qualifications

• 4+ years of Windows Systems Administration in a production environment.
• Deep, hands-on Active Directory expertise: GPO, DNS, DHCP, replication, FSMO, and AD security.
• Strong PowerShell scripting/automation skills.
• Solid Microsoft 365 / Entra ID administration experience (Exchange Online, Conditional Access, MFA).
• Working knowledge of Windows Server, Hyper-V, and core networking (DNS, DHCP, VPN, firewalls).
• Security fundamentals: hardening, least privilege, certificate/PKI basics, and patch management.
• Comfort with version control (Git) and documentation discipline.