Systems Administrator

ManhattanLife; Houston (TX); On-site; USD 90,000 - 140,000; Full time

Benefits offered by this job

Health, dental, vision coverage

Flexible schedules

Fridays shortened hours

Free parking

Company events

Professional development

Wellness program

Job summary

ManhattanLife Insurance and Annuity Company in Houston is seeking a Senior Systems Administrator to own and secure on‑premises infrastructure and integrate cloud services across Windows, Linux, Microsoft 365, and Azure.

You will design, deploy, test, and stabilize systems, implement AD/Entra ID, MFA, SSO, and RBAC, automate with PowerShell and CLI tools, and document everything for operations and support teams.

Qualifications

• Five or more years of hands‑on production infrastructure experience.
• Experience designing and building production infrastructure from requirements through deployment and stabilization.
• Breadth across server, network, identity, cloud, and security domains.

Responsibilities

• Translate requirements into designs, implementation plans, dependencies, change records and rollback plans.
• Configure and place into production on‑prem Windows and Linux servers, virtualization, storage, identity services, and security controls.
• Lead greenfield deployments, migrations, upgrades, and office integrations through validation and stabilization.
• Establish repeatable deployment standards, templates, and automation.

Skills

Windows Server

Active Directory

Azure

Microsoft 365

PowerShell

Security best practices

Documentation

Networking

Education

High School Diploma or equivalent practical experience

Tools

VMware vSphere

Cisco Meraki Firewalls

Azure CLI

Windows/Linux administration

Job description

ManhattanLife Insurance and Annuity Company was founded in 1850, the Company’s longevity makes it one of the oldest and most reliable health and life insurance companies in the country. Operating successfully for over 175 years is a testimony to ManhattanLife’s enduring history, and an indicator of the reliability of our future. ManhattanLife’s headquarters are in Houston, TX and the company is continually growing with multiple office locations nation-wide. ManhattanLife offers attractive employee benefits starting day one, including immediate coverage under our health, dental and vision plans. We offer flexible schedules, including shortened hours on Fridays, free parking, company-wide events, professional development, and a company-wide wellness program.

Scope and Purpose:

This onsite Houston role is for a Senior Systems Administrator who builds, secures, and owns on-premises infrastructure and integrates cloud services. The scope includes Windows, Linux, Microsoft 365, Azure, identity, virtualization, networking, backup, and security. Senior, hands‑on MSP experience is valued, alone or combined with broad enterprise experience. Comparable enterprise‑only implementation experience is welcome.

This hands‑on role owns infrastructure from design through deployment or migration, testing, documentation, and stabilization. Candidates should explain systems they personally built or redesigned and the decisions they owned. Infrastructure fundamentals, security judgment, and ability to learn matter more than knowing every product.

Duties and Responsibilities:

Infrastructure Design & Implementation:

• Translate business and technical requirements into practical designs, implementation plans, dependencies, change records, validation steps, rollback plans, and support documentation.
• Personally configure, integrate, test, and place into production on‑premises Windows and Linux servers, virtualization, storage, backup, identity services, monitoring, security controls, and Cisco or Meraki networks.
• Lead and execute greenfield deployments, migrations, major upgrades, platform replacements, and office integrations through post‑implementation validation and stabilization.
• Establish secure, repeatable deployment standards, templates, and automation, then transition completed systems into documented operational ownership.

Systems, Cloud & Identity:

• Implement and administer Windows Server, Group Policy, DNS, DHCP, file services, permissions, and authentication.
• Implement and administer enterprise Linux, including access, patching, monitoring, troubleshooting, and availability.
• Evaluate and integrate Azure services based on business needs, security, reliability, operational effort, and cost; use managed services where appropriate.
• Implement and administer Active Directory and Entra ID, including MFA, Conditional Access, SSO, federation, identity lifecycle, RBAC, least privilege, and privileged access.
• Administer Microsoft 365 services, including Exchange Online, collaboration, security, compliance, retention, and auditing.
• Implement approved SaaS solutions, configuring SSO, SCIM‑based provisioning and deprovisioning, RBAC, and audit logging where supported; document configurations and operational ownership.
• Automate deployments, configuration, health checks, and reporting with PowerShell, Azure CLI, Bash, APIs, or comparable tools.

Networking, Security & Resilience:

• Implement and support Cisco, Meraki, or comparable firewalls, switches, wireless networks, VPNs, WAN links, and management platforms.
• Troubleshoot TCP/IP, routing, switching, DNS, DHCP, VLANs, segmentation, remote access, and ISP connectivity.
• Implement firewall rules, network segmentation, VPNs, and access controls through documented and approved changes.
• Apply security best practices for hardening, patching, MFA, privileged access, endpoint protection, logging, and vulnerability remediation.
• Support and test backup, restore, replication, and disaster recovery; partner with Security on incident response, audits, and remediation.

Operations, Documentation & Projects:

• Own incidents and problems through diagnosis, communication, root‑cause analysis, resolution, and durable correction.
• Use ITSM, RMM, alerting, and documentation platforms with the discipline expected in a mature MSP or enterprise environment.
• Maintain accurate architecture diagrams, CMDB and inventory records, build standards, runbooks, knowledge articles, and operating procedures.
• Serve as an escalation point and technical mentor for HelpDesk and support teams.
• Plan and deliver infrastructure projects with business teams, vendors, and technology partners.

Minimum Qualifications:

These qualifications describe the work, not a rigid checklist. Candidates with comparable experience are encouraged to apply.

• High School Graduate, GED, or equivalent practical experience.
• Typically five or more years of hands‑on production infrastructure experience; demonstrated capability and breadth matter more than a precise year count.
• Examples of production infrastructure personally designed and built from requirements through deployment, documentation, validation, and stabilization.
• Broad implementation, administration, and troubleshooting experience across multiple infrastructure domains.
• Experience managing tickets, priorities, changes, documentation, and escalations in a production environment.

Knowledge, Skills and Abilities:

• Deep expertise in at least one infrastructure discipline, with the range and judgment to design and troubleshoot beyond it.
• Practical knowledge of secure configuration, least privilege, layered controls, patching, recovery, and change management.
• Ability to evaluate design tradeoffs, identify dependencies and risks, plan validation and rollback, and execute with limited step‑by‑step direction.
• Ability to balance incidents, projects, security remediation, and lifecycle work with clear ownership and communication.
• Strong documentation and communication skills, with a practical approach to standardization, automation, and operational improvement.

Preferred Experience:

These experiences strengthen a candidate’s fit. Comparable hands‑on implementation experience can be considered.

• Senior, hands‑on MSP experience, alone or combined with broad enterprise experience, with ownership of production builds, migrations, upgrades, and complex troubleshooting. Comparable enterprise‑only experience with broad, end‑to‑end implementation responsibility is welcome.
• Hands‑on experience implementing, integrating, and troubleshooting infrastructure across server, network, identity, cloud, and security domains.
• Automation, infrastructure as code, standardization, monitoring improvements, or elimination of recurring manual work.
• Experience supporting regulated environments, HIPAA or PCI controls, audits, M&A integrations, or relevant technical certifications.

Relevant Technology Experience:

• Windows Server, Active Directory, Group Policy, DNS, DHCP, Entra ID, Microsoft 365, Intune/Autopilot and Exchange Online. Azure architecture, hybrid integration, governance, security, and cost management.
• Enterprise Linux, including Red Hat, Rocky Linux, CentOS, Ubuntu, or comparable distributions.
• VMware vSphere, vCenter, ESXi, high availability, storage, and Veeam.
• Cisco Secure Firewall (Firepower), ISE, Meraki, Secure Endpoint, Umbrella, Secure Email, Secure Client (AnyConnect), ThousandEyes, and Duo.
• ConnectWise Manage or Automate, IT Glue, or comparable ITSM, RMM, and documentation tools.

Travel Requirements:

This position may require light travel within a ten‑mile radius from one office location to another as needed within the Houston area.

Professional Development:

• Set annual professional development goals and participate in the evaluation process.
• Maintain current knowledge of relevant infrastructure, cloud, networking, automation, and security technologies.

Physical Demands:

The physical demands described here are representative of those required to perform the essential functions of this job. Reasonable accommodations may enable individuals with disabilities to perform these functions. While performing this job, the employee is regularly required to sit for extended periods; stand; walk; type and use a mouse; use hands to handle or feel objects; reach with hands and arms; and talk or hear. The position may require lifting, pulling, or moving office or desk supplies weighing 10 pounds or more.

The work environment described here is representative of the conditions an employee encounters while performing the essential functions of this job. Reasonable accommodations may be made to enable individuals with disabilities to perform these functions. The employee regularly works in an office environment and routinely uses standard office equipment, including computers, Webex‑enabled phones, office phones, and photocopiers.

Other Duties:

This job description is not intended to provide a comprehensive list of all activities, duties, or responsibilities required of the employee. Nothing in this job description restricts management’s right to assign or reassign duties and responsibilities at any time without notice.

AAP/EEO Statement:

ManhattanLife prohibits discrimination based on race, religion, gender, national origin, age, disability, veteran status, marital status, pregnancy, gender expression or identity, sexual orientation, or any other legally protected status. EOE Employer/Vet/Disabled. ManhattanLife values differences. We are committed to fostering an environment that attracts and retains a diverse workforce. With individuals from a variety of backgrounds, ManhattanLife will be better equipped to serve our customers, increase innovation, and reduce risks. We encourage the unique perspectives of individuals and are dedicated to creating a respectful and inclusive work environment.