Flows and ClusterFlows


For the full details on configuring Flows and ClusterFlows, see the Banzai Cloud Logging operator documentation.

Configuration

Flows

A Flow defines which logs to collect and filter and which output to send the logs to.

The Flow is a namespaced resource, which means logs will only be collected from the namespace that the Flow is deployed in.

Flows can be configured by filling out forms in the Rancher UI.

For more details about the Flow custom resource, see FlowSpec.

Matches

Match statements are used to select which containers to pull logs from.

You can specify match statements to select or exclude logs according to Kubernetes labels, container and host names. Match statements are evaluated in the order they are defined and processed only until the first matching select or exclude rule applies.

Matches can be configured by filling out the Flow or ClusterFlow forms in the Rancher UI.

For detailed examples on using the match statement, see the official documentation on log routing.

Filters

You can define one or more filters within a Flow. Filters can perform various actions on the logs, for example, add additional data, transform the logs, or parse values from the records. The filters in the Flow are applied in the order in the definition.

For a list of filters supported by the Banzai Cloud Logging operator, see this page.

Filters need to be configured in YAML.

Outputs

This Output will receive logs from the Flow. Because the Flow is a namespaced resource, the Output must reside in same namespace as the Flow.

Outputs can be referenced when filling out the Flow or ClusterFlow forms in the Rancher UI.

ClusterFlows

Matches, filters and Outputs are configured for ClusterFlows in the same way that they are configured for Flows. The key difference is that the ClusterFlow is scoped at the cluster level and can configure log collection across all namespaces.

ClusterFlows can be configured by filling out forms in the Rancher UI.

After ClusterFlow selects logs from all namespaces in the cluster, logs from the cluster will be collected and logged to the selected ClusterOutput.

YAML Example

The following example Flow transforms the log messages from the default namespace and sends them to an S3 Output:

  1. apiVersion: logging.banzaicloud.io/v1beta1
  2. kind: Flow
  3. metadata:
  4. name: flow-sample
  5. namespace: default
  6. spec:
  7. filters:
  8. - parser:
  9. remove_key_name_field: true
  10. parse:
  11. type: nginx
  12. - tag_normaliser:
  13. format: ${namespace_name}.${pod_name}.${container_name}
  14. localOutputRefs:
  15. - s3-output
  16. match:
  17. - select:
  18. labels:
  19. app: nginx