Data center Network Architect

Context

Public-sector contract for the ICT department of a major Belgian infrastructure operator, covering the design of the data center network architecture. The mission concerns critical VMware, Oracle, SAN, AI and hybrid Azure environments, in a context of data center network transformation and security hardening.

Mission

Design a future-proof, cloud-connected data center network that takes the existing environment and budget constraints into account. Deliver an approved target architecture and a three-year roadmap for the data center networks.

Responsibilities

- Support the design of a cloud-connected, future-ready data center network, considering:

- deterministic performance for east-west traffic

- secure segmentation and micro-segmentation aligned with Zero Trust principles

- high availability and disaster recovery for critical operations

- hybrid cloud integration with Azure on-premises

- Deliver an approved target architecture and a three-year roadmap: define clear standards, build a migration plan, and document considerations, risks and rationale in an architecture decision record (ADR).

- Assess the current state: inventory the underlay, overlay, SAN, DMZ and edge environments, identify dependencies, establish performance baselines and identify risks.

- Define the target architecture: reference network architectures for VMware, Oracle, SAN or vSAN, AI and Azure on-premises, including the segmentation model and HA/DR designs.

- Select technologies and draft a high-level roadmap: assess EVPN/VXLAN fabrics versus ACI or alternatives, RoCE Ethernet versus InfiniBand for AI interconnect, FC SAN evolution versus NVMe and RoCEv2, micro-segmentation solutions, and Azure Stack HCI and Arc networking.

- Apply security by design: Zero Trust guidelines, micro-segmentation policy, privileged access, traffic encryption and secrets management.

- Analyse performance and capacity: throughput and latency, vMotion and vSAN, backup impact, AI training workloads, QoS and congestion-management strategies.

- Plan resilience and disaster recovery: active-active data centers, stretched clusters where relevant, runbooks and failover tests.

- Ensure interoperability: coexistence of VMware/NSX, Oracle RAC/Exadata, SAN zoning and AI cluster interconnect, plus Azure on-premises and hybrid connectivity.

The mission is structured around architecture deliverables, the roadmap and the decision log (ADR).

Working conditions

- Start: 01/12/2026. End: 30/11/2030.

- On-call availability required.

Profile

- 10+ years of experience.

- At least 2 years in data center network architecture.

- At least 2 years with Cisco ACI multi-fabric.

- At least 2 years with Azure cloud and on-premises (hybrid) implementations.

- At least 2 years in SAN networking.

- At least 2 years implementing VMware ESX and NSX-T.

- At least 5 years of in-depth experience with BGP, VXLAN, EVPN, RoCEv2 and MPLS.

- Dutch or French at C2 level wih the other language at B1 ; English B1 minimum

Technical skills

- Data center networking and in-depth L2/L3 knowledge.

- Underlay/leaf-spine with L3 ECMP.

- Distributed firewalling and micro-segmentation.

- Oracle RAC interconnect and Exadata networking, including latency and bandwidth requirements for Data Guard.

- Backup and restore flows.

- Dual-fabric Fibre Channel (Gen 6/7), zoning and multipathing.

- Lossless Ethernet (PFC/ETS), RDMA/NCCL optimisation and telemetry.

- Scratch/temporary data storage, north-south traffic, private connectivity, identity and policy extension.

- Zero Trust architecture.

- Compliance: ISO 27001, NIS2 and GDPR.

Tools and technologies

Cisco ACI, Azure (Azure Stack HCI, Azure Arc, AKS, ExpressRoute), VMware (ESX, vSphere, VCF, NSX-T, NSX, vSAN), Oracle RAC and Exadata, BGP, VXLAN, EVPN, RoCEv2, MPLS, Fibre Channel, NVMe, RDMA, Ethernet, InfiniBand, MACsec, IPsec, SSL, PKI, KMS.