Network Engineer – Deployment and Support

About the Job

As 'Network Engineer – Deployment and Support' within our Digital Technology Service Quality team, you will deploy, and support the enterprise network that connects Sanofi — LAN and WAN, WLAN, data center fabric, SD-WAN, and cloud networking across AWS and Azure. You will deploy infrastructure as code using Terraform, Ansible, and Python wherever the platform allows, and apply the same engineering rigor where it does not. You will own what you deploy — from design validation and automated pre-change checks through to day-two operations, capacity management, and incident response — ensuring our network estate remains accurate, performant, resilient, and ready for AI-enabled operations. Ready to get started?

Our Team

Digital Technology – Service Quality is at the heart of Sanofi's digital transformation. We deliver secure, resilient, and scalable infrastructure services that power business-critical applications and enable thousands of users across the enterprise. Our network engineering team owns the connectivity that every other service depends on — spanning offices, laboratories, manufacturing sites, data centers, and multiple cloud providers. Our team combines modern cloud platforms, automation-first engineering, and service excellence to support Sanofi's mission of chasing the miracles of science.

About Sanofi

We're an R&D-driven, AI-powered biopharma company committed to improving people's lives and delivering compelling growth. Our deep understanding of the immune system – and innovative pipeline – enables us to invent medicines and vaccines that treat and protect millions of people around the world. Together, we chase the miracles of science to improve people's lives.

Main Responsibilities

Network Deployment – Infrastructure as Code and Automation

Deploy cloud network infrastructure as code using Terraform, provisioning virtual networks and VPCs, subnets, route tables, peering, transit gateway and virtual WAN hubs, VPN gateways, and ExpressRoute and Direct Connect attachments across AWS and Azure, with reusable modules, remote state management, and plan review built into the change process

Deploy and maintain network configuration as code using Ansible, building reusable roles and templates for Cisco IOS and NX-OS, FortiOS, and Junos devices so that every deployment is repeatable, version-controlled, and auditable

Automate network provisioning and operational tasks in Python, consuming platform APIs — Cisco APIC for ACI fabric, Junos Space for Juniper estate management, Prisma SD-WAN and FatPipe controllers, and F5, Array, and AVI load balancer APIs

Automate vendor web consoles and portals that expose no usable API using Selenium, so that carrier portals, licensing, and legacy management interfaces do not force manual work

Use NEXUS as an AI agent within the engineering workflow to accelerate configuration generation and peer review, triage large log and packet-capture data sets, draft runbooks and knowledge articles, and scaffold Ansible and Python automation

Maintain Git as the source of truth for network configuration, with golden configuration templates, peer-reviewed changes, and a full version-controlled audit trail

Operate deployment pipelines for network change, including automated pre-change validation, standards compliance checks, and automated post-deployment verification of routing state, reachability, and interface health

Implement configuration drift detection and automated remediation, so deployed network configuration provably matches its declared intent

Codify network standards — naming, addressing, VLAN and VRF conventions, hardening baselines, and device software targets — and gate deployments against them

Drive deployments from an authoritative source of truth for IP addressing and inventory, rather than from spreadsheets

Implement zero-touch and templated onboarding so new switches, access points, and site routers reach a compliant baseline without manual console configuration

Network Deployment – Engineering Delivery

Deploy network configuration items (CIs) including Cisco IOS and NX-OS switches and routers, Juniper devices, Aruba wireless controllers and access points, load balancers, and network appliances, from initial requirement through to validated production handover

Deliver network deployments at offices, laboratories, manufacturing sites, and on-premises data centres, including physical installation, rack and stack, structured cabling, optics, power and environmental checks, and high-availability pairing

Deliver hardware refresh, end-of-life replacement, and firmware and network OS upgrade campaigns across Cisco IOS/NX-OS, FortiOS, and Junos platforms, including RMA handling across the device estate

Execute controlled environment promotion (Dev to Pre-Prod to Production) with documented rollback and recovery plans for every deployment

Register all deployed CIs in the CMDB with correct class, attributes, relationships, ownership, location, and lifecycle status at point of deployment

Configure and maintain network discovery and SNMP so network CIs are correctly classified with accurate serial numbers, models, and discovery-source behavior

Onboard every newly deployed CI into monitoring, telemetry, configuration backup, and patching tooling before production sign-off

Produce and maintain as-built documentation, network topology diagrams, low-level designs, runbooks, and knowledge articles for all deployed infrastructure

Routing, Switching and Networking Protocols

Implement and support routing across the estate — BGP and OSPF to a strong standard, static routing, route redistribution, filtering, and path selection

Design and implement VRF-based segregation and route separation across data center, campus, and WAN environments

Implement and support switching — VLANs, trunking, spanning tree, link aggregation, vPC, and first-hop redundancy on Cisco IOS and NX-OS platforms

Implement and support IPSec tunnelling for site-to-site and cloud connectivity, including encryption standards, rekeying, and failover behavior

Design and implement addressing and subnetting to enterprise standards, maintaining IP address management accuracy as deployments land

Implement quality of service, multicast, and traffic engineering where application or manufacturing requirements demand it

Implement network zones, VLANs, and segmentation in line with security architecture and zoning standards, in partnership with the network security team

Data Centre, SDN and SD-WAN

Deploy and support data center fabrics built on Cisco ACI, using Cisco APIC for policy, tenant, and endpoint group configuration, and VXLAN overlays for tenant connectivity

Deploy and support leaf-spine data center architectures, including fabric expansion, overlay design, and integration with compute and storage connectivity requirements

Deploy and support SD-WAN across Palo Alto Prisma SD-WAN (CloudGenix) and FatPipe platforms, including overlay design, transport independence, application-aware routing policy, and failover behavior

Coordinate circuit delivery with carriers and service providers, managing lead times, handover testing, and acceptance

Monitor and manage WAN capacity, latency, and cost, recommending upgrades, re-homing, or transport changes

Wireless Networking – WLAN

Deploy, configure, and support Aruba wireless infrastructure, including controllers, access points, and centralized WLAN management

Deliver wireless design and validation, including predictive design, site surveys, RF tuning, channel and power planning, and post-deployment validation surveys

Support wireless authentication integration and guest access in partnership with the network security and identity teams

Troubleshoot wireless performance, roaming, coverage, and interference issues, including in warehouse, laboratory, and manufacturing environments

Core Network Services