Feature Gates

Feature gates are a set of key-value pairs that control the behavior of NFD. They are used to enable or disable certain features of NFD. The feature gates are set using the -feature-gates command line flag or featureGates value in the Helm chart. The following feature gates are available:

NodeFeatureAPI

The NodeFeatureAPI feature gate enables the NodeFeature API (the NodeFeature custom resource) as the communication channel between nfd-worker and nfd-master. The feature gate is GA since NFD v0.17 and locked to true: setting -feature-gates=NodeFeatureAPI=false fails with "cannot set feature gate NodeFeatureAPI to false, feature is locked to true". The gate will be removed in a future release. The NFD custom resource definitions are installed by the deployment (the Helm chart or the kustomize base), not by NFD itself.

NodeFeatureGroupAPI

The NodeFeatureGroupAPI feature gate enables processing of NodeFeatureGroup objects in nfd-master. When enabled, nfd-master evaluates the rules of each NodeFeatureGroup in its own namespace and writes the matching nodes to the object's status. The NodeFeatureGroup CRD is installed by the deployment regardless of this gate; with the gate disabled such objects can be created but their status is never updated. The Node Feature Group API is an alpha feature and is disabled by default.

DisableAutoPrefix

The DisableAutoPrefix feature gate controls the automatic prefixing of names. When enabled nfd-master does not automatically add the default feature.node.kubernetes.io/ prefix to unprefixed labels, annotations and extended resources. Automatic prefixing is the default behavior in NFD v0.16 and earlier.

For example, with the DisableAutoPrefix feature gate set to false, a NodeFeatureRule with

  labels:
    foo: bar

will be automatically prefixed, resulting in the node label feature.node.kubernetes.io/foo=bar. However, when DisableAutoPrefix is set to true, no prefix is added, and the label remains as foo=bar. Note that taint keys are not affected by this feature gate.

Note: nfd-master does not remove the unprefixed labels, annotations and extended resources that it created while this gate was enabled when they are no longer produced, for example when the NodeFeatureRule is deleted or changed, or when the gate is set back to false. They stay on the node until removed manually:

kubectl label node <node> <key>-
kubectl annotate node <node> <key>-
kubectl patch node <node> --subresource=status --type=json \
  -p '[{"op":"remove","path":"/status/capacity/<name>"},{"op":"remove","path":"/status/allocatable/<name>"}]'