Senior Linux SysAdmin – Security & Hardened Ops

CACI International; National Harbor (MD); On-site; USD 104,000 - 218,000; Full time

Job summary

CACI International is seeking a Linux System Administrator to support FEMA's OCISO in Washington, D.C. You will secure Linux infrastructure, implement STIGs or CIS benchmarks, and work with cybersecurity professionals to maintain secure server configurations across on-premises and hybrid environments.

Responsibilities include hardening services, patching, monitoring health and capacity, managing identities with ICAM tools, and ensuring high availability for mission-critical systems.

Qualifications

• U.S. Citizenship required
• FEMA EOD suitability or Current DHS or FEMA EOD preferred
• 7+ years of applicable experience in Linux system administration
• Minimum 7 years of experience in Linux system administration
• Demonstrated expertise in Linux infrastructure, DISA STIGs, and CIS Benchmarks
• Experience with security hardening and vulnerability remediation
• Knowledge of firewalls, access controls, and system service hardening
• Experience with LDAP, PAM, and identity management solutions
• Strong understanding of Linux security logging and monitoring.

Responsibilities

• Secure Linux-based infrastructure for FEMA enterprise and leverage STIGs or CIS Benchmarks to reduce attack surfaces.
• Configure firewalls, access controls, and harden system services; perform regular patching and upgrades.
• Remediate vulnerabilities and plan/test patches to avoid operational disruptions.
• Ensure high availability and uptime for mission-critical systems; monitor performance, health and capacity.
• Manage user identities, authentication, authorization; support ICAM tools, LDAP, and privileged access management.
• Implement principle of least privilege and maintain system logging for auditing and compliance.
• Support vulnerability remediation and security assessments; stay current on threats and defenses.
• Research and apply best practices to protect Linux systems.

Skills

Linux System Administration

DISA STIGs

CIS Benchmarks

Security hardening

LDAP / IAM

Firewalls

PAM / Identity management

Shell scripting (bash, python)

Automation tools (Ansible, Puppet,Chef

Hybrid cloud (AWS, Azure)

Tools

Ansible

Puppet

Chef

Job description

CACI International is seeking a Linux System Administrator to support FEMA's OCISO in Washington, D.C. You will secure Linux infrastructure, implement STIGs or CIS benchmarks, and work with cybersecurity professionals to maintain secure server configurations across on-premises and hybrid environments.

Responsibilities include hardening services, patching, monitoring health and capacity, managing identities with ICAM tools, and ensuring high availability for mission-critical systems.