Senior Systems Admin Engineer – TS/SCI with Poly

Cricket Wireless LLC.; Chantilly (VA); On-site; USD 98,000 - 220,000; Full time

Benefits offered by this job

Medical/Dental/Vision coverage

401(k) plan

Tuition reimbursement program

Paid Time Off and Holidays

life and disability benefits

Job summary

AT&T Global Public Sector seeks a Senior Security Engineer to manage security operations, system administration, and compliance across Linux/Windows environments and virtualization platforms. This role requires active TS/SCI clearance with polygraph and US citizenship, with onsite work in Chantilly, VA.

You will lead security tooling, patching, vulnerability remediation, and documentation efforts while mentoring junior staff and coordinating with ISSOs/ISSMs to ensure accreditation readiness.

Qualifications

• Bachelor's degree and minimum 5 years of relevant experience in Security operations of systems supporting virtualization, Windows and Linux computing solution engineering and architecture solutions.
• Experience with on-premise, cloud and hybrid-cloud based deployments.
• US citizenship is required.
• Active federal security clearance.
• Strong written and verbal communication skills.

Responsibilities

• Administer and maintain Linux-based operating systems and virtualization platforms (Red Hat, CentOS, Ubuntu, VMware, KVM, QEMU/KVM, Hyper-V).
• Support Windows server and workstation environments, including enterprise deployments.
• Provide multi-platform support for OEM appliances and VMware-based Windows and Linux virtual appliances.
• Mentor junior and mid-level team members on installation procedures and security-focused administration.
• Install, configure, operate, and maintain security and analysis tools such as Trellix, SentinelOne, Nessus, Splunk.
• Perform system patching, vulnerability remediation, and hardening activities for systems and networks.
• Deliver Tier 1 through Tier 3 technical support and collaborate with Tier 2 teams.
• Produce and maintain OPS policies/instructions, CONOPS, SECOPS, and system build documents.

Skills

Security operations

Virtualization

Windows/Linux computing

Team leadership

Education

Bachelor's degree

Tools

ITSM

ServiceNow

Job description

AT&T Global Public Sector seeks a Senior Security Engineer to manage security operations, system administration, and compliance across Linux/Windows environments and virtualization platforms. This role requires active TS/SCI clearance with polygraph and US citizenship, with onsite work in Chantilly, VA.

You will lead security tooling, patching, vulnerability remediation, and documentation efforts while mentoring junior staff and coordinating with ISSOs/ISSMs to ensure accreditation readiness.