A custom resource definition (CRD) extends the Kubernetes API with a new resource type. The Fluent Operator uses CRDs to represent Fluent Bit deployment and configuration concerns as Kubernetes resources, allowing operators to assemble logging behavior from declarative objects. section 4.8
The Fluent Operator defines several CRDs with distinct operational roles:
- FluentBit defines node monitoring through a DaemonSet, including the container image and configuration. section 4.8
- ClusterFluentBitConfig defines cluster-wide input, output, and filter configurations, with optional namespace targeting. section 4.8
- FluentBitConfig selects namespace-level inputs, outputs, filters, and parsers using the same conventions as cluster-level configuration. section 4.8
Listing 4.10 Helm chart config: fluentbit_v1alpha2_fluentbitconfig.yaml
apiVersion: fluentbit.fluent.io/v1alpha2
kind: FluentBitConfig
metadata:
name: fluentbitconfig-sample
spec:
service: #1
flush: 1
daemon: false
logLevel: info
parsersFile: parsers.conf
inputSelector: #2
matchExpressions: #3
- key: fluentbit.fluent.io/enabled
operator: In
values: ["true"] #4
filterSelector: #5
matchExpressions:
- key: fluentbit.fluent.io/enabled
operator: In
values: ["true"]
outputSelector:
matchExpressions:
- key: fluentbit.fluent.io/enabled
operator: In
values: ["true"]
Inspect a FluentBitConfig custom resource that selects enabled inputs, filters, and outputs through label-based match expressions. section 4.8
