Senior Linux System Administrator

Senior Linux System Administrator The Senior Linux System Administrator will be responsible for operating, maintaining, securing, and automating Red Hat, Ubuntu, and other Linux systems across on-premises and Azure environments, including Azure Commercial/GCC and Azure Government. The ideal candidate will have strong Linux administration experience combined with hands-on knowledge of Azure, Azure DevOps, Docker, security hardening, automation, and identity management. Key Responsibilities: Administer, configure, troubleshoot, and maintain production and non-production RHEL and Ubuntu servers and VMs. Perform CIS-aligned Linux security hardening and remediation. Work with Microsoft Defender for Cloud and Azure Policy for security posture and compliance. Manage Ubuntu patching using Ubuntu Pro, Livepatch, ESM, and APT. Develop and maintain automation using Bash and PowerShell, including Cron-based scheduled jobs. Support Azure DevOps repositories, pipelines, CI/CD workflows, and Linux-based deployments. Support Docker workloads running on standalone Linux VMs. Integrate container workloads with Azure Key Vault and Azure Container Registry (ACR). Manage SSSD identity integration, sudoers governance, and PAM configuration. Administer LVM, XFS/EXT4 filesystems, partitions, and dedicated mounts such as /var, /tmp, and /var/log/audit. Support audit findings, auditd logging, compliance activities, and cybersecurity initiatives. Troubleshoot and optimize Linux systems while maintaining security and availability. Required Qualifications: 8+ years of hands-on Linux system administration experience in enterprise or government environments. Strong expertise with current Ubuntu Server LTS releases and RHEL. Experience administering Linux VMs in Microsoft Azure. Knowledge of Azure networking, managed identities, and Key Vault. Hands-on experience with Azure DevOps, repositories, pipelines, and CI/CD. Experience with Docker on Linux, including container secrets management. Advanced Bash scripting and working knowledge of PowerShell. Strong knowledge of UFW, SSH hardening, AppArmor, and SSL/TLS certificates. Experience with systemd, /etc/sysctl.conf, PAM, auditd, and log rotation. Ability to work independently within a small, cross-functional IT/security team. Preferred Qualifications: Ubuntu/Canonical certifications, CISSP, or CompTIA Security+. AZ-900 and/or AZ-104 certification. Healthcare or public-sector IT experience. Familiarity with MARS-E, HIPAA technical safeguards, or CMS security requirements. Experience supporting development infrastructure with rapidly changing workloads. About Us: InterSources Inc, a Certified Diverse Supplier, was founded in 2007 and offers innovative solutions to help clients with Digital Transformations across various domains and industries. Our history spans over 19 years and today we are an Award-Winning Global Software Consultancy solving complex problems with technology. We recognize that our employees and our clients are our strengths as the diverse talents and opportunities they bring to the table enable us to grow as a global platform and they are causally linked with our success. We provide strategic and technical advice, and we have expertise in areas covering Artificial Intelligence, Cloud Migration, Custom Software Development, Data Analytics Infrastructure & Cloud Solutions, Cyber Security Services, etc. We make reasonable accommodations for clients and employees and we do not discriminate based on any protected attribute including race, religion, color, national origin, gender sexual orientation, gender identity, age, or marital status. We also are a Google Cloud partner company. We align strategy with execution and provide secure service solutions by developing and using the latest technologies that thrive our resources to deliver industry-leading capabilities to our clients and customers, making it convenient for our clients to do business with InterSources Inc. Our teams also drive growth by refining technology-driven client experiences that put the users first, providing an unparalleled experience. This results in strengthening the core technologies of clients, enabling them to scale with flexibility, create seamless digital experiences and build lifelong relationships. InterSources