Linux Engineer

The Phoenix Group; New York (NY); On-site; USD 120,000 - 150,000; Full time

Job summary

The Phoenix Group in New York is seeking a seasoned Linux systems engineer to manage a mixed fleet of Ubuntu and RHEL servers for high-availability, high-concurrency sessions.

You will secure handoffs between RDP gateways and backend SSH environments, optimize Nginx as a reverse proxy, and tune the Linux networking stack to prevent bottlenecks while supporting data replication to SQL Server environments and ETL pipelines.

Qualifications

• Hands-on admin of Ubuntu and RHEL in high-concurrency production environments.
• Proficient with Nginx, kernel/network tuning, and SSH hardening.
• Familiar with Postfix, CUPS, SELinux, and AppArmor.
• Knowledge of ETL pipelines and SQL Server replication.
• Strong diagnostic skills and methodical troubleshooting.
• Experience ensuring high availability and secure handoffs in complex networks.

Responsibilities

• Manage and optimize a mixed fleet of Ubuntu and RHEL servers, maintaining high availability for large volumes of concurrent remote sessions
• Oversee secure handoffs between RDP gateways and backend SSH environments
• Configure and tune Nginx as a high-performance reverse proxy and load balancer under peak traffic conditions
• Monitor and tune the Linux networking stack to prevent bottlenecks in high-density session environments
• Monitor and maintain outbound data feed replication from Linux-based systems to Microsoft SQL Server environments
• Ensure the integrity of automated ETL scripts and data pipelines across heterogeneous systems

Skills

Ubuntu/RHEL admin

Nginx & network tuning

SSH hardening

Postfix/CUPS/SELinux/AppArmor

ETL pipelines & SQL Server replication

Troubleshooting

Tools

Nginx

SQL Server

Postfix

CUPS

SELinux

AppArmor

Job description

• Manage and optimize a mixed fleet of Ubuntu and RHEL servers, maintaining high availability for large volumes of concurrent remote sessions
• Oversee secure handoffs between RDP gateways and backend SSH environments
• Configure and tune Nginx as a high-performance reverse proxy and load balancer under peak traffic conditions
• Monitor and tune the Linux networking stack (TCP/IP limits, file descriptors, socket buffers) to prevent bottlenecks in high-density session environments

Critical Services & Messaging Operations

• Manage Postfix mail queues for transactional messaging and internal relay operations
• Support enterprise-scale printing via CUPS, resolving driver conflicts and spooling issues across a distributed environment

Security & Hardening

• Apply security best practices across Ubuntu and RHEL fleets using SELinux, AppArmor, and firewall configurations to maintain a defense-in-depth posture
• Harden SSH configurations and access entry points to limit lateral movement risk

Data Integration Support

• Monitor and maintain outbound data feed replication from Linux-based systems to Microsoft SQL Server environments
• Ensure the integrity of automated ETL scripts and data pipelines across heterogeneous systems

Qualifications

• Strong hands-on experience administering Ubuntu and RHEL in high-concurrency production environments
• Proficiency with Nginx, Linux kernel and network tuning, and SSH hardening
• Working knowledge of Postfix, CUPS, SELinux, and AppArm
• Familiarity with ETL pipelines and SQL Server replication
• Strong diagnostic instincts and a methodical approach to troubleshooting