Building reliable multi-cloud infrastructure

Multi-cloud is often sold as insurance. In practice it is a second operating model: identity, networking, deployment, data gravity, and incident response all have to exist twice — or they have to be abstracted with honesty about what that costs.

Reliability does not come from running the same workload in two regions of two clouds. It comes from knowing which failure domains you actually need, and designing failover that has been rehearsed.

A workable pattern is to be multi-cloud at the program level, not at every microservice. Shared controls, distinct landing zones, and a small set of portable interfaces (identity, observability, artifact flow) beat a lowest-common-denominator platform.

Data is the constraint. If the database cannot move, the application’s multi-cloud story is a traffic and compute story only. Say that plainly in the architecture, or the DR plan will lie.

Treat multi-cloud as a project with a charter: which risks it reduces, which it introduces, and who owns the control plane on each provider. Without that, it is just twice the configuration.