Senior Network Administrator — Onsite, High-Impact Networking

Apex Systems; Alexandria (VA); Hybrid; USD 95,000 - 125,000; Full time

Benefits offered by this job

ESPP (Employee Stock Purchase Program)

401K with company match

Health Savings Account (HSA)

Employee Assistance Program (EAP)

Certification discounts

Job summary

Everforth Apex Systems in Alexandria, VA is seeking a Senior Network Administrator to maintain secure, high‑performing network services on-site. You will work with engineers, admins, and security teams to troubleshoot, design, and implement network solutions that support critical missions.

Required: 3+ years of experience, CCNA and Security+ certifications, TCP/IP, VLANs, VPN, and Cisco ISE/DNA Center proficiency. TS/SCI eligibility is preferred, and 100% on-site work is expected.

Qualifications

• 3+ years of Network Administrator experience.
• Experience configuring switches and routers.
• Strong understanding of TCP/IP, DNS, DHCP, STP, SNMP, and routing fundamentals.
• Hands-on with Cisco ISE and DNA Center (DNA-C).
• Knowledge of firewalls, ACLs, NAT, and VPN technologies.

Responsibilities

• Troubleshoot incidents and implement network changes.
• Participate in design discussions and deployments.
• Support Cisco ISE and DNA Center for access control and policy automation.
• Implement VLANs, routing policies, and network segmentation.
• Maintain secure environments with firewall rules and VPNs.
• Document activities and follow change management processes.

Skills

Network troubleshooting

TCP/IP fundamentals

DNS & DHCP

VLANs & routing

Firewall & VPN basics

RADIUS & 802.1X

Wireshark / NetFlow

Cisco ISE & DNA Center

Documentation

Education

High School diploma

Tools

Cisco ISE

DNA Center

Wireshark

NetFlow

Job description

Everforth Apex Systems in Alexandria, VA is seeking a Senior Network Administrator to maintain secure, high‑performing network services on-site. You will work with engineers, admins, and security teams to troubleshoot, design, and implement network solutions that support critical missions.

Required: 3+ years of experience, CCNA and Security+ certifications, TCP/IP, VLANs, VPN, and Cisco ISE/DNA Center proficiency. TS/SCI eligibility is preferred, and 100% on-site work is expected.