Senior Network Engineer Level 3 (ON-SITE WALLINGFORD, CT)

Systems Integration Inc.; Wallingford (CT); On-site; USD 95,000 - 130,000; Full time

Job summary

Systems Integration Inc. in Wallingford, CT is seeking a Senior Network Engineer for an in-person role. You will lead complex IT infrastructure projects, mentor junior staff, and serve as Tier 3 escalation for client deployments within a busy MSP setting.

The position emphasizes hands-on network design, Microsoft 365/Azure, virtualization, and security technologies. You will collaborate with vCIO and project managers to scope, plan, and execute initiatives, maintaining documentation and

Qualifications

• 5+ years IT experience in MSP or multi-client environment.
• Strong Windows Server, Active Directory, Azure, and M365 administration.
• Advanced networking knowledge: firewalls, routing, switching, VLANs, SD-WAN.
• Experience with virtualization: VMware/Hyper-V.
• Expertise in endpoint security, patching, and RMM tools.
• Proven project leadership and cross-team coordination.
• Excellent verbal and written communication skills.
• Valid U.S. driver’s license and reliable transportation.
• Availability for after-hours support and on-call when needed.

Responsibilities

• Lead the implementation and support of complex IT infrastructure projects (server migrations, network redesigns, cloud transitions).
• Configure and troubleshoot advanced network devices (firewalls, Layer 2/3 switches, VLANs, VPN tunnels, routing policies).
• Deploy and manage Microsoft 365 services (Exchange Online, Teams, SharePoint, Intune, CA).
• Administer Azure AD, Azure VMs, Group Policy, DNS/DHCP, file/print services, and hybrid environments.
• Implement and manage backup and disaster recovery solutions (Datto, Veeam, or similar).
• Provide Tier 3 support and final escalation point for unresolved issues.
• Conduct site assessments, document environments, and propose improvements.
• Collaborate with vCIO and project managers to scope, plan, and execute IT initiatives.
• Mentor Level 1/2 technicians and transfer knowledge on resolutions and best practices.
• Contribute to SOPs, security baselines, and deployment templates.
• Maintain documentation and diagrams in AutoTask and related systems.

Skills

MSP environment experience

Windows Server

Active Directory

Azure

M365 administration

Networking concepts

Firewalls

SD-WAN

VLANs

VMware

Hyper-V

Endpoint security

RMM tools

Troubleshooting

Project leadership

Communication skills

Driver's license

On-call readiness

Tools

AutoTask

IT Glue

VMware

Hyper-V

Job description

THIS IS AN IN-PERSON ROLE, 5 DAYS A WEEK, WITH TRAVEL TO WALLINGFORD, CT DAILY.

THIS IS NOT A DEVELOPER ROLE.

We are seeking an experienced and highly skilled Level 3 Senior Network Engineer to lead complex technical implementations, serve as an escalation point for junior technicians, and support infrastructure and cloud projects across our client base. This role is ideal for a seasoned professional with strong hands‑on experience in network design, Microsoft 365/Azure, virtualization, server environments, and firewall/security technologies within a Managed Services Provider (MSP) setting.

As a Senior Engineer, you will manage project scopes, act as technical lead for client deployments, and provide Tier 3 escalation support. You will mentor other team members, help refine internal processes, and ensure client solutions align with industry best practices and business goals.

We are looking for an individual who is a problem‑solver and has a proven track record of working within a team environment to address challenging user computing issues successfully, and is accustomed to leveraging technical training opportunities to improve their skills.

Accountabilities include identifying user problems and working within structured problem management and resolution processes to remediate them within established SLAs, and involve working with other resources and vendors to deliver effective support services. Includes identifying, documenting, and troubleshooting user computing issues to resolution and maintaining customer satisfaction.

Responsibilities and Duties

• Lead the implementation and support of complex IT infrastructure projects (server migrations, network redesigns, cloud transitions).
• Configure and troubleshoot advanced network devices (firewalls, Layer 2/3 switches, VLANs, VPN tunnels, routing policies).
• Deploy and manage Microsoft 365 services (Exchange Online, Teams, SharePoint, Intune, Conditional Access).
• Administer Azure AD, Azure VMs, Group Policy, DNS/DHCP, file/print services, and hybrid environments.
• Implement and manage backup and disaster recovery solutions (Datto, Veeam, or similar).
• Provide Tier 3 support and serve as the final escalation point for unresolved issues.
• Conduct site assessments, document technical environments, and make recommendations for improvements.
• Collaborate with vCIO and project managers to scope, plan, and execute IT initiatives.
• Mentor Level 1 and Level 2 technicians and provide knowledge transfer for issue resolution and best practices.
• Contribute to the development and improvement of technical SOPs, security baselines, and deployment templates.
• Maintain current technical documentation, network diagrams, and project notes in AutoTask and related systems.

Qualifications

Required

• 5+ years of progressive IT experience in an MSP or multi-client environment.
• Strong technical proficiency in Windows Server environments, Active Directory, Azure, and M365 administration.
• Advanced knowledge of networking concepts (firewalls, routing, switching, VLANs, SD-WAN).
• Experience implementing and supporting virtualization platforms (VMware, Hyper-V).
• Expertise with endpoint security, patching, and RMM tools.
• Excellent troubleshooting and analytical skills for root cause analysis and problem resolution.
• Proven ability to lead IT projects and coordinate with internal teams and client stakeholders.
• Exceptional verbal and written communication skills.
• Valid U.S. driver's license and reliable transportation.
• Availability for after-hours support and on-call responsibilities when needed.

Preferred

• Relevant certifications such as Microsoft 365 Enterprise Administrator Expert, Cisco CCNA/CCNP, Fortinet NSE4+, VMware VCP, or Azure Administrator Associate.
• Familiarity with PSA and documentation platforms (AutoTask, IT Glue).