Senior Systems & Security Administrator — Hybrid Infra Lead

The Phoenix Group®; United States; Hybrid; USD 120,000 - 160,000; Full time

Job summary

The Phoenix Group® is seeking a hands-on Senior Systems & Security Administrator to own its infrastructure, security operations, and automation. You’ll work with leadership to strengthen security posture, keep systems resilient, and support compliance goals.

Responsibilities include managing hybrid environments, Entra ID, M365, Intune, Autopatch, patching, incident response, vulnerability management, backups, audits, and automation with PowerShell and Graph.

Qualifications

• 5+ years in systems administration, including senior level in production environments.
• Experience within formal compliance frameworks such as ISO 27001, SOC 2, NIST CSF, or HIPAA.
• Deep knowledge of Microsoft cloud stack, enterprise networking, and endpoint security.

Responsibilities

• Run the firm's hybrid environment (cloud and on premises) across offices, endpoints, network gear, and security tooling.
• Own identity and access in Entra ID: user lifecycle, MFA, conditional access, SSO, and privileged accounts.
• Administer Microsoft 365 (Exchange Online, SharePoint, OneDrive, Teams, Purview) and manage devices via Intune and Autopatch.
• Maintain firewalls, VLANs, wireless, VPN, and web filtering.
• Monitor EDR and DLP tools (SentinelOne, Defender), triage alerts, and coordinate with outsourced SOC.
• Lead incident response from containment through recovery, including root cause reviews.
• Drive vulnerability management, patching, and pen test remediation.
• Build and enforce change management, hardening standards, and update procedures.
• Manage backups and DR, including restore testing and business continuity exercises.
• Track hardware, licenses, and secure media disposal; custodianship of encryption keys.
• Support audits and ISO 27001 certification work.
• Automate routine tasks with PowerShell, Graph, and native workflows, document everything.

Skills

Cloud security

ISO 27001 / SOC 2 / NIST CSF

Microsoft 365 security

PowerShell / Graph scripting

Documentation & runbooks

Security incident response

Tools

Intune

Autopatch

SentinelOne

Defender

Job description

The Phoenix Group® is seeking a hands-on Senior Systems & Security Administrator to own its infrastructure, security operations, and automation. You’ll work with leadership to strengthen security posture, keep systems resilient, and support compliance goals.

Responsibilities include managing hybrid environments, Entra ID, M365, Intune, Autopatch, patching, incident response, vulnerability management, backups, audits, and automation with PowerShell and Graph.