Glossary & concepts

Concepts

Short explanations of concepts used across the test plans — networking, storage, secrets management, and more — for anyone who does not work with them every day.

macvtap (NOT supported) vs. OVN-K localnet (official path)

macvtap gives a VM its own MAC — but is NOT officially supported in OpenShift Virtualization. The correct approach is OVN-K localnet.

WaitForFirstConsumer (StorageClass binding mode)

A PVC stays deliberately 'Pending' until a pod/VM actually uses it — not an error!

NodeNetworkConfigurationPolicy (NNCP)

Declarative node network configuration via the Kubernetes API — instead of manual nmcli commands.

An NNCP is a Kubernetes resource that tells the NMState Operator how the network on one or more nodes should be configured. NMState translates this into NetworkManager configuration on the node — persistent across reboots. Without NMState, you would run ip-link/nmcli commands manually on each node, and they would be lost after a reboot.

✓ ADVANTAGES

Persistent across reboot
Declarative and versionable like all Kubernetes resources
Works cluster-wide via nodeSelector (e.g. configure all workers at once)

⚠ LIMITATIONS

Changes to interfaces already managed by OVN-K (e.g. br-ex) are risky
A faulty NNCP can break node connectivity completely — test carefully!

📍 WHY IT MATTERS HERE

Used in PRE-03 (operator installation) and PRE-04 (creating bridges/VLANs) — all bridge and VLAN configuration in this test plan runs through NNCP.

OVN-Kubernetes & br-ex

OpenShift's default network plugin uses an OVS bridge (br-ex) that takes over the physical NIC.

HCP: does every hosted cluster need its own public IP?

No — only the API server (with the KubeVirt/on-prem provider) needs a dedicated IP or dedicated port. OAuthServer, Konnectivity, and Ignition already share the management cluster's existing Ingress route today.

Sealed vs unsealed — why pods stay 0/1 Ready

A sealed OpenBao holds only encrypted data and refuses almost every request — the pod runs but is not Ready. Unsealing reconstructs the barrier key.

KV v2 — versions, soft delete, and check-and-set (CAS)

KV v2 keeps a version history per secret and can require a version number on every write — a write is a whole new version, not a field update.

Kubernetes auth method — SA token in, OpenBao token out

Pods authenticate with their projected ServiceAccount JWT; OpenBao validates it against the kube-apiserver and returns a short-lived token carrying the role's policies.

OpenBao vs Vault — why /vault/ still appears everywhere

OpenBao is the Linux Foundation fork of HashiCorp Vault and keeps API and tooling compatibility — so UI routes, sidecar paths, and third-party integrations still say 'vault'.

Raft integrated storage — leader, quorum, snapshots

OpenBao stores data itself and replicates it with the Raft consensus protocol — no external database, but quorum rules apply.

📚 Glossary & concepts

Glossary & concepts