Network Engineer, AI Network & Security

Firmus Technologies Firmus Technologies is a global leader pioneering the development and operation of efficient AI infrastructure across Asia Pacific. Founded in Australia in 2019, our mission is to create the most efficient AI infrastructure by combining cutting-edge technology with a steadfast commitment to sustainability. At Firmus, we are unique in our approach. We design, build, and operate a new class of digital infrastructure – the AI Factory. Through our model-to-grid technology approach, we have pushed the boundaries of multi-generational liquid cooling systems, energy management, AI software orchestration, and construction. For our customers, this approach allows us to make every watt count and deliver low-cost AI tokens globally. Firmus AI Cloud Our large-scale GPU cloud platform, Firmus AI Cloud, is purpose-built to deliver energy-efficient AI compute at scale to customers. It empowers developers, enterprises, educational institutions, and government users to train and deploy AI models with unmatched efficiency and cost savings. With an ever-growing suite of services and applications, we are committed to delivering a cloud experience that is market-leading, proprietary, and built to scale. Why you’ll love working here As an NVIDIA Cloud and Engineering partner in Asia Pacific, you will gain skills, experience, and exposure across the AI industry and be part of shaping what this industry looks like for decades to come. We are founder-led, not a big corporate. Decisions happen fast, our leaders are accessible, and there's minimum bureaucracy between you and the work. Ownership comes early. Whatever your role, you will have a direct line to outcomes, helping shape how the business grows as we scale nationally across a long-term, large-scale roadmap. Work alongside founders and experts in AI infrastructure, energy systems and next-generation compute. What we build here has impact beyond the business. Our AI Factories are designed to operate as assets to the energy grid to actively strengthen the communities and regions they operate in rather than drawing from them. Role Summary Firmus Technologies is seeking a skilled Network Engineer / Sr. Network Engineer to join our Engineering and Technology team. The ideal candidate will play a crucial role in leading the development of our network designs and supporting the network deployment for AI infrastructure projects. This role offers an exciting opportunity to work at the forefront of AI networking technology and contribute to the growth of AI infrastructure. Key Responsibilities • Deploy and Operate High-Performance Networks • Deploy and maintain low-latency, high-throughput interconnects (e.g.: Ethernet 100/200/400GbE) for HPC and AI workloads. • Optimise performance across multi-node clusters, high-speed storage fabrics and parallel computing AI environments. • Respond to and resolve escalated network issues, outages and performance degradations across the SMC Corporate and Compute network infrastructure. • Analyse logs, run diagnostics and coordinate with vendors, carriers as needed. • Work with internal observability team to setup and maintain monitoring tools to proactively identify bottlenecks, errors and abnormal behaviours. • Analyse trends for bandwidth, hardware utilisation, and growth to inform scaling and make recommendations to procurement decisions. • Participate in the operations standby roster and on-call from time to time, and work closely with other network engineers as a team. • Design and test redundant paths, failover mechanisms and DR playbooks to ensure uninterrupted connectivity during outages or maintenance. • InfiniBand/Ethernet and RDMA Networking • Design, monitor and troubleshoot InfiniBand/Ethernet fabrics and RDMA-enabled transport layers. • Maintain subnet managers (e.g.: Unified Fabric Manager and OpenSM) and ensure fabric health and topology visibility. • Perform verification and acceptance tests to the new fabric and new network infrastructure setups. • Understand various InfiniBand / RoCE optimisation protocols and mechanisms (e.g.: SHARP, CollNet) and use performance tools (e.g.: ibstat, perfquery, ib_write_bw, nccl, etc) to monitor fabric health, congestion and link errors. • Enable optimised networking for AI frameworks and work closely with GPU compute environments to ensure efficient multi-node communication. • Perform deep dive diagnostics to resolve layer 1-4 issues across HPC and AI workloads. • Network as Code and Automation • Develop and maintain automated network configurations using Infrastructure as Code (IaC) tools (e.g.: Ansible, Netbox, Python scripts). • Implement CI/CD pipelines for network changes to improve speed, consistency, and auditability. • Automate routine tasks such as provisioning, backups and compliance checks. • Network Security and Policy Enforcement • Implement and manage firewall and security devices. Apply firewall rules, segmentation, and Secure-by-default, Security-by-design principles to safeguard internal and external connectivity. • Collaborate with Security and Risk team to enforce policies and respond to security incidents. • Design and implement zero-trust network architecture across corporate and AI compute fabric, including segmentation and least-privilege access. • Implement authentication and access control (802.1X, NAC, MACsec) for fabric and out-of-band management networks. • Own network security posture for RDMA/RoCEv2 and InfiniBand fabrics, including multi-tenant workload isolation. • Support vulnerability management: coordinate scanning, patching cadence, and remediation tracking for network infrastructure. • Participate in security incident response — detection, containment, root cause analysis, and post-incident reporting — with the SMC Security and Risk team. • Contribute to compliance and audit activity (e.g. ISO 27001, SOC 2) relating to network controls. • Integrate network telemetry and logs w…