Senior Network Engineer - 6 Month - South East London - Outside IR35

We are seeking a highly skilled Senior Network Engineer to architect, deploy, and operate the high-throughput, low-latency network fabric powering our cutting-edge GPU clusters. You'll collaborate closely with Systems, DevOps, and AI Platform teams to ensure our infrastructure meets the extreme demands of modern AI training and inference workloads.

Key Responsibilities:

• Design & Implementation: Architect and roll out leaf-spine fabrics using Mellanox Switches with Cumulus Linux; integrate Juniper PTX core Routers and SRX Firewalls.
• Operations & Maintenance: Perform hands-on configuration, upgrades, and troubleshooting of Juniper PTX, SRX, and NVIDIA/Cumulus devices.
• Automation & Scripting: Develop and maintain Ansible playbooks (and other frameworks) to streamline deployment, configuration management, and compliance.
• Monitoring & Performance Tuning: Implement telemetry and monitoring solutions (eg, SNMP, sFlow, gRPC) to proactively detect and resolve bottlenecks under production loads.
• Incident Response: Lead network incident investigations, root-cause analyses, and post-mortem reviews in a high-pressure, 24×7 operational environment.
• Collaboration & Documentation: Work cross-functionally with compute and storage teams; create detailed documentation for network designs, runbooks, and SOPs.

Essential Skills & Experience:

• HPC/AI Networking: 3-5+ years' experience supporting high-pressure HPC or AI-focused environments, particularly GPU clusters.
• Network Services Expertise: Strong background in BGP, EVPN, VXLAN, MPLS, and Data Center Interconnects (DCI).
• Mellanox Ethernet Switches: Hands-on administration of Mellanox hardware.
• Cumulus Linux: Deep knowledge of L3 leaf-spine architectures and switch management with Cumulus OS.
• Juniper PTX & JUNOS: Advanced configuration, scaling, and troubleshooting of PTX core Routers.
• Juniper SRX: Firewall deployment, configuration, and policy management.
• Linux Proficiency: Comfortable with CLI-based troubleshooting and Scripting.
• Automation: Experience with Ansible and Python Scripting; familiarity with Terraform is a bonus.

Preferred Qualifications:

• Professional certifications such as JNCIE, CCIE, or equivalent.
• Knowledge of network security frameworks and compliance best practices.
• Familiarity with hybrid-cloud networking (eg, AWS or Azure Direct Connect).
• Hands-on experience with network telemetry and observability tools.

Contract Details:

• Start Date: ASAP
• Duration: 6 months
• Location: South East London
• IR35 Status: Outside IR35
• Day Rate: £650PD - £700PD

Senior Network Engineer - 6 Month - South East London - Outside IR35