Multisite Network Administrator - Firewalls, VPNs & On-Call

Certex-USA-In; Houston (TX); On-site; USD 75,000 - 85,000; Full time

Benefits offered by this job

Uniforms Provided

Boot Allowance

Vacation & Sick Leave

Holidays

401k with Match

Medical, Dental, Vision

Life Insurance

Job summary

CERTEX USA, LLC seeks an experienced Network Administrator in Houston to keep branch networks and communications running smoothly. You will install, monitor, and troubleshoot firewalls, switches, and wireless systems across locations, coordinating with ISPs and vendors to ensure uptime.

The role emphasizes security, documentation, and on-call readiness, with a strong collaboration across IT teams to support projects and keep employees connected.

Qualifications

• Bachelor's degree or 4+ years of related experience.
• 3–5 years of hands-on firewall admin in a multi-site environment; SonicWall preferred.
• Experience with branch networks and security across multiple locations.
• Industry experience in construction/oil & gas or similar heavy-industry sectors preferred.

Responsibilities

• Set up and maintain network equipment across branch locations.
• Manage firewalls, switches, and wireless systems for reliability.
• Troubleshoot network issues beyond the IT Service Desk.
• Support backup Internet connections to prevent outages.
• Monitor network performance and document changes.
• Coordinate with ISPs/vendors to install services.
• Assist with network security improvements across teams.
• Maintain network diagrams and records and ensure reliable communications.

Skills

Firewall admin

Multi-site networking

VPN & security

Vendor coordination

On-call support

Remote monitoring

Documentation

Cloud networking

VoIP knowledge

Network security

Troubleshooting

Education

Bachelor's in MIS/CIS

4+ years experience

Tools

SonicWall

Cambium

Aruba

Ubiquiti

Meraki

Job description

CERTEX USA, LLC seeks an experienced Network Administrator in Houston to keep branch networks and communications running smoothly. You will install, monitor, and troubleshoot firewalls, switches, and wireless systems across locations, coordinating with ISPs and vendors to ensure uptime.

The role emphasizes security, documentation, and on-call readiness, with a strong collaboration across IT teams to support projects and keep employees connected.