Senior Linux Administrator

Seneca Resources; Montgomery (AL); On-site; USD 90,000 - 130,000; Full time

Job summary

Seneca Resources is seeking a senior Linux Administrator to manage production and non-production Linux environments. You will implement CIS security hardening, patch management, and automation across Ubuntu and RHEL, while coordinating with security teams on Azure and Docker workloads.

The role requires extensive experience with Ubuntu Server, Azure, and Docker on Linux, plus strong scripting skills in Bash and PowerShell and identity management with SSSD.

Qualifications

• 8+ years of hands-on Linux administration in enterprise or government environments.
• Strong experience with Ubuntu Server LTS releases.
• Working knowledge of Microsoft Azure supporting Linux VMs, including networking, Managed Identity, and Azure Key Vault.
• Experience with Azure DevOps, including repositories, pipelines, and CI/CD workflows.
• Experience administering Docker on Linux, including container secrets management.
• Advanced Bash scripting and working knowledge of PowerShell.
• Experience with UFW, SSH hardening, AppArmor, and SSL/TLS certificate management.
• Experience with systemd, kernel tuning/sysctl, PAM, auditd, and log rotation.
• Experience with SSSD and Linux identity/access management.
• Experience with LVM and XFS/EXT4 filesystem administration.
• Ability to independently troubleshoot and administer enterprise Linux environments.

Responsibilities

• Administer, configure, troubleshoot, and maintain Linux servers (RHEL/Ubuntu) in production and non-production environments.
• Maintain CIS-aligned security hardening and configurations (UFW, SSH, AppArmor, PAM, auditd, SSL/TLS).
• Support security compliance and remediation using Azure security tooling and Defender for Cloud.
• Manage Ubuntu patching and lifecycle activities using Ubuntu Pro, Livepatch, ESM, and APT.
• Develop and maintain automation using Bash and PowerShell, including Cron jobs.

Skills

Linux administration

Enterprise Linux

Ubuntu Server

Microsoft Azure

Azure DevOps

Docker on Linux

Bash scripting

PowerShell

Security hardening

Systemd & kernel tuning

SSSD identity management

LVM and XFS/EXT4

Tools

Azure DevOps

Docker

UFW

AppArmor

Job description

• Administer, configure, troubleshoot, and maintain production and non-production RHEL and Ubuntu Linux virtual and physical servers.
• Maintain CIS-aligned security hardening, including UFW, SSH, AppArmor, PAM, auditd, and SSL/TLS configurations.
• Support security compliance and remediation using Microsoft Defender for Cloud, Azure Policy, and Azure-native security tooling.
• Manage Ubuntu patching and lifecycle activities using Ubuntu Pro, Livepatch, Extended Security Maintenance (ESM), and APT.
• Develop and maintain automation using Bash and PowerShell, including Cron jobs and scheduled processes.
• Support Azure DevOps repositories, pipelines, source control, and CI/CD workflows for Linux environments.
• Support Docker workloads running on standalone Linux VMs.
• Integrate containerized workloads with Azure Key Vault for secrets management.
• Support Azure Container Registry (ACR), including image push/pull operations and vulnerability scanning.
• Maintain SSSD-based identity integration, sudoers governance, and PAM configuration.
• Manage LVM, XFS/EXT4 filesystems, partitions, and dedicated mounts in accordance with CIS guidance.
• Perform system administration involving systemd, kernel tuning, auditd, and log rotation.
• Partner with cybersecurity teams to address audit findings, logging requirements, remediation activities, and overall security posture.
• Work independently as the senior Linux resource within a small, cross-functional IT and security team.

Required Qualifications

• 8+ years of hands-on Linux administration experience in enterprise or government environments.
• Strong experience with current Ubuntu Server LTS releases.
• Working knowledge of Microsoft Azure supporting Linux VMs, including networking, Managed Identity, and Azure Key Vault.
• Experience with Azure DevOps, including repositories, pipelines, and CI/CD workflows.
• Experience administering Docker on Linux, including container secrets management.
• Advanced Bash scripting skills and working knowledge of PowerShell.
• Experience with UFW, SSH hardening, AppArmor, and SSL/TLS certificate management.
• Experience with systemd, kernel tuning/sysctl, PAM, auditd, and log rotation.
• Experience with SSSD and Linux identity/access management.
• Experience with LVM and XFS/EXT4 filesystem administration.
• Ability to independently troubleshoot and administer enterprise Linux environments.