Senior System Administrator (Linux)

TISTA Science and Technology is seeking a Senior System Administrator to join our growing team.

At TISTA, you’ll do meaningful, mission‑driven work that improves lives alongside teammates you trust and leaders who are transparent and supportive. We invest in your learning and internal mobility so you can build a career that keeps advancing. We’re proud to serve and hire Veterans, and we put people first in everything we do.

TISTA associates enjoy above Industry Healthcare Benefits, Remote Working Options, Paid Time Off, Training/Certification opportunities, Healthcare Savings Account & Flexible Savings Account, Paid Life Insurance, Short-term & Long-term Disability, 401K Match, Professional development reimbursement, Employee Assistance Program, Paid Holidays, Military Leave, and much more!

• Install, configure, maintain, and troubleshoot enterprise Linux systems including Red Hat Enterprise Linux and Solaris.
• Manage user accounts, permissions, and authentication services.
• Perform patch management, upgrades, and lifecycle planning.
• Maintain storage, file systems, backups, and recovery procedures.
• Administer virtual environments.
• Support hybrid cloud infrastructure in Amazon Web Services and Microsoft Azure.
• Maintain core network services (DNS, DHCP, NFS, SSH, VPN).
• Develop scripts using Bash, Python, or similar languages.
• Implement automation using Ansible and Puppet.
• Automate provisioning, patching, compliance checks, and deployments.
• Implement system hardening, access controls, and security best practices.
• Manage firewalls, SELinux, and intrusion detection measures.
• Monitor logs and perform vulnerability remediation.
• Support compliance requirements such as CIS benchmarks, NIST, or HIPAA (if applicable).
• Implement system monitoring using Nagios, Zabbix, or Prometheus.
• Analyze performance metrics and optimize system resources.
• Perform root cause analysis and implement preventative solutions.
• Provide Tier III support and technical leadership.
• Mentor junior system administrators and support staff.
• Collaborate with cybersecurity, networking, and application teams.
• Develop and maintain technical documentation and procedures.

• 5+ years of advanced Linux system administration experience.
• Expertise managing enterprise Linux environments.
• Experience with virtualization and cloud platforms.
• Strong scripting and automation skills.
• Participation in on-call rotation and maintenance windows may be required.
• Work may be performed in data center, cloud, and secure environments.

Core Competencies:

• Enterprise Linux administration.
• Automation & Infrastructure as Code.
• Security & compliance best practices.
• Cloud and virtualization technologies.
• Advanced troubleshooting & performance tuning.
• Documentation & operational excellence.

Preferred Certifications:

• Red Hat Certified Engineer (RHCE).
• Linux Foundation certifications (LFCS/LFCE).
• AWS or Azure cloud certifications.

Education:

• Bachelor’s degree in computer science, electronics engineering or related technical discipline and 5+ years’ work experience.
• Eight (8) years of additional relevant experience may be substituted for education (13 years total).

Clearance: 

• The ability to pass a Tier 4/HIGH Background Investigation.

Location:

• Department of Veteran's Affairs (100% On-site).
• Sunday - Thursday  (3:30 AM - 12:00 AM EST Time).
• Austin Information Technology Center (AITC).

1615 Woodward Street,

Austin, TX 78741