Linux Engineer

The Phoenix Group; City of White Plains (NY); On-site; USD 110,000 - 150,000; Full time

Benefits offered by this job

Health insurance

401(k)

Paid time off

Professional development opportunities

Job summary

The Phoenix Group Advisors is seeking a Senior Linux Systems Engineer to manage high-density Linux server infrastructures and support enterprise operations in a fast-paced environment.

You will optimize Ubuntu/RHEL environments, tune web services with Nginx, and harden security across systems while collaborating with development and application teams on integrations and performance issues.

Qualifications

• Proven hands-on experience managing Ubuntu and RHEL in high-concurrency production environments.
• Strong expertise in Linux system tuning, network configuration, and kernel parameters.
• Proficiency with web server configuration and performance optimization, especially Nginx.
• Experience with Linux security hardening including SELinux, AppArmor, SSH configurations, and firewall management.
• Familiarity with Postfix mail queue management, CUPS printing services, and related hardware/software support.
• Understanding of data ETL pipelines, data replication, and workflows involving SQL Server or similar databases.
• Excellent troubleshooting skills with a logical, analytical approach.

Responsibilities

• Manage and optimize a mixed fleet of Linux servers (Ubuntu and RHEL), ensuring high availability and performance for thousands of concurrent users and remote sessions.
• Configure, tune, and maintain web server platforms, including Nginx as a reverse proxy and load balancer under peak traffic conditions.
• Monitor and optimize Linux networking components to prevent bottlenecks in high-density session environments.
• Support critical messaging and printing services, including Postfix email queues, enterprise printing solutions (CUPS), and related hardware/software integration.
• Harden Linux systems using security best practices, including SELinux, AppArmor, firewalls, and SSH hardening to minimize security risks.
• Oversee data integration and replication workflows, including monitoring data feeds and maintaining automated ETL processes between Linux environments and SQL Server infrastructure.
• Collaborate with development teams on application support, API integrations, and troubleshooting performance issues related to system resource utilization.
• Diagnose and troubleshoot system and network issues, employing methodical approaches to resolve performance bottlenecks and system irregularities.

Skills

Ubuntu

RHEL

Nginx

Linux tuning

Security hardening

Postfix

CUPS

ETL

SQL Server

Troubleshooting

Tools

tcpdump

netstat

ps

top

htop

systemd

Job description

Role Overview This position involves managing high-density Linux server infrastructures, ensuring reliable performance, and collaborating closely with application and development teams to support enterprise operations. The engineer will focus on high-availability server management, system tuning, security hardening, and supporting data integration workflows in a fast-paced, high-volume environment.

Key Responsibilities

• Manage and optimize a mixed fleet of Linux servers (Ubuntu and RHEL), ensuring high availability and performance for thousands of concurrent users and remote sessions
• Configure, tune, and maintain web server platforms, including Nginx as a reverse proxy and load balancer under peak traffic conditions
• Monitor and optimize Linux networking components such as TCP/IP stack, socket buffers, and file descriptors to prevent bottlenecks in high-density session environments
• Support critical messaging and printing services, including Postfix email queues, enterprise printing solutions (CUPS), and related hardware/software integration
• Harden Linux systems using security best practices, including SELinux, AppArmor, firewalls, and SSH hardening to minimize security risks and lateral movement
• Oversee data integration and replication workflows, including monitoring data feeds and maintaining automated ETL processes between Linux environments and SQL Server infrastructure
• Collaborate with development teams on application support, API integrations, and troubleshooting performance issues related to system resource utilization, particularly in environments involving COBOL-based applications running on Linux
• Diagnose and troubleshoot system and network issues, employing methodical approaches to resolve performance bottlenecks and system irregularities

Core Qualifications & Requirements

• Proven hands‑on experience managing Ubuntu and RHEL in high‑concurrency, production environments
• Strong expertise in Linux system tuning, network configuration, and kernel parameters
• Proficiency with web server configuration and performance optimization, especially Nginx
• Experience with Linux security hardening including SELinux, AppArmor, SSH configurations, and firewall management
• Familiarity with Postfix mail queue management, CUPS printing services, and related hardware/software support
• Understanding of data ETL pipelines, data replication, and workflows involving SQL Server or similar databases
• Excellent troubleshooting skills with a logical, analytical approach
• Ability to learn new systems quickly and adapt to evolving operational needs
• Critical thinker with strong problem‑solving skills and the capacity to work collaboratively with cross‑functional teams

Nice-to-Have Qualifications

• Experience supporting COBOL-based applications and understanding of legacy system integration
• Knowledge of site reliability engineering principles and practices
• Familiarity with scripting languages such as Bash, Python, or Perl for automation
• Exposure to cloud environments and containerization tools (e.g., Docker, Kubernetes)
• Prior experience working with enterprise POS systems and associated backend infrastructure

Core Technical Skills

• Linux administration (Ubuntu, RHEL, CentOS)
• Web server platforms: Nginx, Apache
• Linux network tuning and kernel parameter optimization
• Security hardening: SELinux, AppArmor, SSH hardening, firewall configuration
• Messaging systems: Postfix, enterprise email protocols
• Printing systems: CUPS, hardware/software integration
• Data workflows: ETL, data replication, SQL Server connectivity
• Monitoring and troubleshooting tools: tcpdump, netstat, ps, top, htop, Systemd

Career Impact This role offers the chance to lead mission‑critical Linux infrastructure operations, influence system security, and contribute to high‑availability enterprise processes, making a significant impact on core business operations.

Compensation and Benefits Competitive salary package based on experience, plus comprehensive benefits including health insurance, 401(k), paid time off, and professional development opportunities.

The Phoenix Group Advisors is an equal opportunity employer. We are committed to creating a diverse and inclusive workplace and prohibit discrimination and harassment of any kind based on race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, genetic information, disability, or veteran status. We strive to attract talented individuals from all backgrounds and provide equal employment opportunities to all employees and applicants for employment.