About logging 6.0 - Logging | Observability | OpenShift Container Platform 4.15

Inputs and Outputs
Receiver Input Type
Pipelines and Filters
Operator Behavior
Validation
- Quick Start

The ClusterLogForwarder custom resource (CR) is the central configuration point for log collection and forwarding.

Inputs and Outputs

Inputs specify the sources of logs to be forwarded. Logging provides built-in input types: application, infrastructure, and audit, which select logs from different parts of your cluster. You can also define custom inputs based on namespaces or pod labels to fine-tune log selection.

Outputs define the destinations where logs are sent. Each output type has its own set of configuration options, allowing you to customize the behavior and authentication settings.

Receiver Input Type

The receiver input type enables the Logging system to accept logs from external sources. It supports two formats for receiving logs: http and syslog.

The ReceiverSpec defines the configuration for a receiver input.

Pipelines and Filters

Pipelines determine the flow of logs from inputs to outputs. A pipeline consists of one or more input refs, output refs, and optional filter refs. Filters can be used to transform or drop log messages within a pipeline. The order of filters matters, as they are applied sequentially, and earlier filters can prevent log messages from reaching later stages.

Operator Behavior

The Cluster Logging Operator manages the deployment and configuration of the collector based on the managementState field:

When set to Managed (default), the operator actively manages the logging resources to match the configuration defined in the spec.
When set to Unmanaged, the operator does not take any action, allowing you to manually manage the logging components.

Validation

Logging includes extensive validation rules and default values to ensure a smooth and error-free configuration experience. The ClusterLogForwarder resource enforces validation checks on required fields, dependencies between fields, and the format of input values. Default values are provided for certain fields, reducing the need for explicit configuration in common scenarios.

Quick Start

Prerequisites

Cluster administrator permissions

Procedure

Install the OpenShift Logging and Loki Operators from OperatorHub.

Create a LokiStack custom resource (CR) in the openshift-logging namespace:

apiVersion: loki.grafana.com/v1
kind: LokiStack
metadata:
  name: logging-loki
  namespace: openshift-logging
spec:
  managementState: Managed
  size: 1x.extra-small
  storage:
    schemas:
    - effectiveDate: '2022-06-01'
      version: v13
    secret:
      name: logging-loki-s3
      type: s3
    storageClassName: gp3-csi
  tenants:
    mode: openshift-logging

Create a service account for the collector:

$ oc create sa collector -n openshift-logging

Create a ClusterRole for the collector:

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: logging-collector-logs-writer
rules:
- apiGroups:
  - loki.grafana.com
  resourceNames:
  - logs
  resources:
  - application
  - audit
  - infrastructure
  verbs:
  - create

Bind the ClusterRole to the service account:

$ oc adm policy add-cluster-role-to-user logging-collector-logs-writer -z collector

Install the Cluster Observability Operator.

Create a UIPlugin to enable the Log section in the Observe tab:

apiVersion: observability.openshift.io/v1alpha1
kind: UIPlugin
metadata:
  name: logging
spec:
  type: Logging
  logging:
    lokiStack:
      name: logging-loki

Add additional roles to the collector service account:

$ oc project openshift-logging
$ oc adm policy add-cluster-role-to-user collect-application-logs -z collector
$ oc adm policy add-cluster-role-to-user collect-audit-logs -z collector
$ oc adm policy add-cluster-role-to-user collect-infrastructure-logs -z collector

Create a ClusterLogForwarder CR to configure log forwarding:

apiVersion: observability.openshift.io/v1
kind: ClusterLogForwarder
metadata:
  name: collector
  namespace: openshift-logging
spec:
  serviceAccount:
    name: collector
  outputs:
  - name: default-lokistack
    type: lokiStack
    lokiStack:
      target:
        name: logging-loki
        namespace: openshift-logging
    authentication:
      token:
        from: serviceAccount
    tls:
      ca:
        key: service-ca.crt
        configMapName: openshift-service-ca.crt
  pipelines:
  - name: default-logstore
    inputRefs:
    - application
    - infrastructure
    outputRefs:
    - default-lokistack

Verify that logs are visible in the Log section of the Observe tab in the OpenShift web console.

Logging 6.0