Glossary

Hub — the authoritative Moodle in a federation. Holds the canonical course catalogue, optionally the canonical user identity. Every Nucleus customer has exactly one hub.

Spoke — a downstream Moodle that federates from a hub. Each spoke is its own tenant: own database, own namespace, own users.

Federation — the contract between a hub and its spokes. Modes are described in Concepts → Federation.

Mode A — content federation. The hub publishes courses; spokes consume them. Identity is per-spoke.

Mode B — identity federation. Users sign in once at the hub and pass through to the spoke.

Control plane — the backend that orchestrates lifecycle: provisioning, upgrades, federation, billing. Talks to Kubernetes via Helm.

Tenant — a hub or a spoke. A complete Moodle instance with its own data.

Tier — pricing band. Standard runs spokes on shared cluster nodes; Dedicated runs on isolated nodes with stricter SLAs.

Size — per-spoke pod resources. Small / Medium / Large, mapped to CPU + memory limits.