The Senior Systems & Network Engineer (L3) serves as the highest technical escalation point for complex infrastructure, cloud, network, and security issues across multiple client environments. This role is responsible for designing, implementing, optimizing, and supporting enterprise-grade IT infrastructure while ensuring high availability, security, scalability, and operational excellence.
As an L3 Engineer, you will lead complex troubleshooting efforts, perform deep root cause analysis (RCA), and drive long-term solutions rather than temporary fixes. You will collaborate with internal engineering teams, mentor junior engineers, and participate in infrastructure modernization projects involving Microsoft 365, Azure, VMware, networking, cybersecurity, disaster recovery, and automation.
This role requires exceptional technical expertise, strong analytical skills, and the ability to manage multiple enterprise environments within a Managed Service Provider (MSP) setting.
Key ResponsibilitiesInfrastructure Engineering- Design, implement, and maintain enterprise Windows Server environments (2012–2025).
- Architect and manage Active Directory, Azure Active Directory (Entra ID), DNS, DHCP, DFS, PKI, Certificate Services, File Services, and Group Policy.
- Design and administer hybrid Microsoft 365 and Azure environments.
- Plan and execute infrastructure upgrades, migrations, consolidations, and modernization projects.
- Perform capacity planning, performance tuning, and infrastructure optimization.
- Design, deploy, and troubleshoot enterprise LAN, WAN, SD-WAN, VLANs, VPNs, routing, switching, wireless networks, and high-availability architectures.
- Configure and support Cisco, Meraki, SonicWall, Fortinet, Palo Alto, Ubiquiti, and similar enterprise networking platforms.
- Troubleshoot complex routing protocols, VPN tunnels, firewall policies, NAT, ACLs, QoS, and network segmentation.
- Support multi-site and Site-to-Site VPN environments.
- Administer Microsoft 365, Exchange Online, SharePoint Online, Teams, OneDrive, Defender, and Intune.
- Design Conditional Access policies, MFA, Autopilot deployments, compliance policies, and endpoint security.
- Perform advanced Exchange administration, including hybrid Exchange environments.
- Design and manage enterprise Group Policy Objects (GPOs) and security baselines.
- Design and administer VMware vSphere, ESXi, vCenter, Hyper-V, and clustered virtualization environments.
- Manage storage, snapshots, HA, DRS, vMotion, replication, and virtual networking.
- Design and support Microsoft Azure infrastructure, including virtual networks, virtual machines, storage, identity, backup, monitoring, and governance.
- Support cloud migration and hybrid cloud initiatives.
- Implement Zero Trust security principles and identity management best practices.
- Configure Microsoft Defender, Sentinel, Azure Security Center, Conditional Access, and endpoint security solutions.
- Perform vulnerability assessments, security remediation, patch management, and hardening activities.
- Investigate security incidents and assist with incident response and remediation.
- Ensure compliance with industry standards and security best practices.
- Design and maintain backup and disaster recovery solutions using Veeam, Datto, Barracuda, Azure Backup, and similar technologies.
- Perform backup validation, recovery testing, replication monitoring, and disaster recovery planning.
- Conduct periodic recovery drills and document recovery procedures.
- Develop automation scripts using PowerShell and other scripting technologies.
- Improve operational efficiency through automation, standardization, and process optimization.
- Build documentation, knowledge base articles, SOPs, and infrastructure standards.
- Identify recurring issues and implement permanent corrective actions.
- Serve as the final escalation point for complex infrastructure, networking, virtualization, and cloud issues.
- Perform advanced Root Cause Analysis (RCA) and implement permanent resolutions.
- Lead major incident investigations and post-incident reviews.
- Coordinate with vendors, Microsoft, hardware manufacturers, ISPs, and third-party providers during critical incidents.
- Mentor and coach L1 and L2 engineers through technical guidance and knowledge sharing.
- Participate in technical reviews, project planning, and change management.
- Collaborate with cross-functional teams to deliver infrastructure projects on time.
- Maintain accurate technical documentation and ensure adherence to ITIL best practices.
Requirements
- Bachelor's degree in Computer Science, Information Technology, Engineering, or a related field (or equivalent professional experience).
- 5–8+ years of experience in Systems Administration, Network Engineering, Infrastructure Engineering, or a senior MSP environment.
- Extensive experience supporting enterprise-level Microsoft, networking, virtualization, and cloud technologies.
- Strong experience working in Managed Service Provider (MSP) environments supporting multiple clients.
- Windows Server 2012–2025
- Active Directory
- Azure Active Directory (Entra ID)
- Microsoft 365
- Exchange Online & Hybrid Exchange
- SharePoint Online
- Teams
- OneDrive
- Intune
- Group Policy
- DNS
- DHCP
- DFS
- PKI
- Certificate Services
- PowerShell
- Cisco
- Meraki
- SonicWall
- Fortinet
- Palo Alto
- Ubiquiti
- VLANs
- Routing & Switching
- Site-to-Site VPN
- SSL VPN
- SD-WAN
- TCP/IP
- DNS
- NAT
- ACLs
- QoS
- Wireless Networking
- VMware ESXi
- VMware vCenter
- VMware HA
- DRS
- vMotion
- Hyper-V
- Storage Management
- Microsoft Azure
- Azure Virtual Machines
- Azure Networking
- Azure Storage
- Azure Backup
- Azure Monitor
- Azure Security
- Hybrid Cloud Infrastructure
- Veeam
- Datto
- Barracuda
- Microsoft Defender
- Sentinel
- Endpoint Detection & Response (EDR)
- Vulnerability Management
- Disaster Recovery
- Business Continuity
- ConnectWise
- Kaseya
- Datto RMM
- NinjaOne
- N-able
- IT Glue
- ServiceNow
- Remote Monitoring & Management (RMM)
- Remote Desktop Protocol (RDP)
- Microsoft Certified: Azure Administrator Associate
- Microsoft Certified: Azure Solutions Architect Expert
- Microsoft Certified: Enterprise Administrator Expert
- VMware VCP
- Cisco CCNP
- Fortinet NSE
- Palo Alto PCNSE
- ITIL Foundation
- CompTIA Security+
Benefits
- 🏥 HMO Coverage
- 📋 Government-Mandated Benefits (SSS, PhilHealth, Pag-IBIG, 13th Month Pay)
- 🏠 Work-From-Home Setup
- 🌍 Work with International Clients and Enterprise Environments
- 🚀 Career Growth & Leadership Opportunities
- 📈 Continuous Technical Training & Certification Support
- 🤝 Collaborative Engineering Culture
- 💻 Company Equipment Provided (after 3 months)
Skills Required
- Bachelor's degree in Computer Science, IT, Engineering or equivalent experience
- 5-8+ years experience in Systems Administration, Network Engineering, Infrastructure Engineering, or senior MSP environment
- Experience designing and supporting Windows Server environments (2012-2025) and enterprise Active Directory/Entra ID
- Extensive Microsoft 365 administration (Exchange Online, SharePoint, Teams, OneDrive) and hybrid Exchange experience
- Enterprise networking design and troubleshooting experience (Cisco, Meraki, Fortinet, Palo Alto, SonicWall, Ubiquiti; routing, switching, VPNs, SD-WAN)
- Virtualization and cloud experience (VMware ESXi/vCenter, vMotion, HA, DRS, Hyper-V, Azure infrastructure and migrations)
- Backup and disaster recovery technologies experience (Veeam, Datto, Barracuda, Azure Backup) and recovery testing
- Security and compliance skills: Zero Trust, Defender, Sentinel, EDR, vulnerability management, incident response, patching and hardening
- PowerShell scripting and automation for operational efficiency and process improvement
- Experience using MSP tools and RMM/PSA platforms (ConnectWise, Kaseya, Datto RMM, NinjaOne, N-able, IT Glue, ServiceNow)
- Proven ability to mentor L1/L2 engineers, lead escalations, and perform root cause analysis
- Microsoft Certified: Azure Administrator Associate, Azure Solutions Architect, Enterprise Administrator, VMware VCP, Cisco CCNP, Fortinet NSE, Palo Alto PCNSE, ITIL Foundation, CompTIA Security+
What We Do
Technology, when paired with the right people, unlocks remarkable growth. That’s the belief behind every solution delivered by Prime System Solution. We bring together the top 1% of global talent to help businesses build smarter systems, reduce operational friction, and stay ahead in today’s competitive landscape. With delivery hubs in Pakistan, the Philippines, and the UAE, and clients across North America, Europe, and the MENA region, the reach is global and the focus is personal. Rooted in a culture of collaboration, innovation, and inclusivity, every team is built to perform because success isn’t just about tools and tech, it’s about the people who power it. Our Core Services: Managed Services Talent Providing on-demand IT and Finance professionals to help organizations scale quickly, reduce hiring costs, and stay competitive. From Cybersecurity specialists, Cloud architects, and Data Scientists to Accountants, Financial Analysts, and Payroll experts. IT Consulting: Guiding businesses through digital transformation with expertise in Cloud, Cybersecurity, Artificial Intelligence, Data Science, and IT Infrastructure to achieve operational excellence. Financial Consulting: Enabling CFOs, startups, and enterprises to make smarter decisions with consulting in Accounting, FP&A, Risk Management, and Business Advisory for sustainable growth. We provide you with the resources so that you can unlock borderless growth.
