A hybrid cloud architecture spans on-prem or co-located infrastructure and one or more public cloud computing providers, with workloads that truly move between them. It is powerful, it is sometimes necessary, and it is where a lot of enterprise clouds quietly buckle.
When hybrid actually makes sense
- Data residency or regulatory constraints that pin a subset of workloads to a region or on-prem facility.
- Significant sunk cost in specialised hardware (HPC, storage arrays, network gear).
- Latency requirements that cloud regions cannot meet.
- Gradual migration strategy where on-prem will coexist with cloud for years.
Many "hybrid" architectures are just incomplete migrations with a press release. If there is no ongoing reason for workloads to span on-prem and cloud, consolidate.
The five pillars of a clean hybrid architecture
- Unified identity — one source of truth for users, service accounts, and roles.
- Private connectivity — Direct Connect, ExpressRoute, or equivalent, with redundancy.
- Consistent networking — IP planning, DNS, and segmentation that works identically on both sides.
- Data placement strategy — authoritative copies, replication, and egress costs modelled up front.
- Platform tooling — CI/CD, observability, and policy that works the same regardless of where a workload runs.
Data — the part everyone underestimates
Data gravity is real. A workload that reads a terabyte from a database every hour is not going to live happily a few hundred milliseconds away from it. Before you design the compute plane, decide where the data lives, where copies live, and what egress will cost.
Picking cloud computing providers for hybrid
AWS, Azure, and GCP each bring a hybrid story that fits different estates. If your on-prem identity runs on Active Directory, Azure Arc and Azure Stack HCI integrate more naturally. If you are Kubernetes-heavy, GCP Anthos and EKS Anywhere both deliver consistent control planes. AWS Outposts is the cleanest fit for a heavy AWS customer that needs an on-prem pocket.
Anti-patterns we see over and over
- Cross-cloud chatty services — expensive, slow, and fragile.
- Two identity systems that never reconcile.
- Observability that shows cloud clearly and on-prem as a black box.
- No cost allocation — hybrid without FinOps is hybrid in the dark.