bitnamicharts/grafana-loki repository overview

⁠Bitnami Secure Images Helm chart for Grafana Loki

Grafana Loki is a horizontally scalable, highly available, and multi-tenant log aggregation system. It provides real-time long tailing and full persistence to object storage.

Overview of Grafana Loki⁠

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

⁠TL;DR

helm install my-release oci://registry-1.docker.io/bitnamicharts/grafana-loki

⁠Why use Bitnami Secure Images?

Those are hardened, minimal CVE images built and maintained by Bitnami. Bitnami Secure Images are based on the cloud-optimized, security-hardened enterprise OS Photon Linux⁠. Why choose BSI images?

• Hardened secure images of popular open source software with Near-Zero Vulnerabilities
• Vulnerability Triage & Prioritization with VEX Statements, KEV and EPSS Scores
• Compliance focus with FIPS, STIG, and air-gap options, including secure bill of materials (SBOM)
• Software supply chain provenance attestation through in-toto
• First class support for the internet’s favorite Helm charts

Each image comes with valuable security metadata. You can view the metadata in our public catalog here⁠. Note: Some data is only available with commercial subscriptions to BSI⁠.

If you are looking for our previous generation of images based on Debian Linux, please see the Bitnami Legacy registry⁠.

⁠Introduction

Bitnami charts for Helm are carefully engineered, actively maintained and are the quickest and easiest way to deploy containers on a Kubernetes cluster that are ready to handle production workloads.

This chart bootstraps a Grafana Loki⁠ Deployment in a Kubernetes⁠ cluster using the Helm⁠ package manager.

⁠Prerequisites

• Kubernetes 1.23+
• Helm 3.8.0+
• PV provisioner support in the underlying infrastructure

⁠Installing the Chart

To install the chart with the release name my-release:

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/grafana-loki

The command deploys grafana-loki on the Kubernetes cluster in the default configuration. The Parameters⁠ section lists the parameters that can be configured during installation.

⁠Configuration and installation details

⁠Resource requests and limits

Bitnami charts allow setting resource requests and limits for all containers inside the chart deployment. These are inside the resources value (check parameter table). Setting requests is essential for production workloads and these should be adapted to your specific use case.

To make this process easier, the chart contains the resourcesPreset values, which automatically sets the resources section according to different presets. Check these presets in the bitnami/common chart⁠. However, in production workloads using resourcesPreset is discouraged as it may not fully adapt to your specific needs. Find more information on container resource management in the official Kubernetes documentation⁠.

⁠Rolling VS Immutable tags⁠

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

⁠Loki configuration

The loki configuration file loki.yaml is shared across the different components: distributor, compactor, ingester, querier and queryFrontend. This is set in the loki.configuration value. Check the official Loki Grafana documentation⁠ for the list of possible configurations.

⁠Prometheus metrics

This chart can be integrated with Prometheus by setting metrics.enabled to true. This will expose the Grafana Loki native Prometheus port in both the containers and services. The services will also have the necessary annotations to be automatically scraped by Prometheus.

⁠Prometheus requirements

It is necessary to have a working installation of Prometheus or Prometheus Operator for the integration to work. Install the Bitnami Prometheus helm chart⁠ or the Bitnami Kube Prometheus helm chart⁠ to easily have a working Prometheus in your cluster.

⁠Integration with Prometheus Operator

The chart can deploy ServiceMonitor objects for integration with Prometheus Operator installations. To do so, set the value metrics.serviceMonitor.enabled=true. Ensure that the Prometheus Operator CustomResourceDefinitions are installed in the cluster or it will fail with the following error:

no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"

Install the Bitnami Kube Prometheus helm chart⁠ for having the necessary CRDs and the Prometheus Operator.

⁠Additional environment variables

In case you want to add extra environment variables (useful for advanced operations like custom init scripts), you can use the extraEnvVars property inside each of the subsections: distributor, compactor, ingester, querier, queryFrontend and vulture.

compactor:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

distributor:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

ingester:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

querier:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

queryFrontend:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

vulture:
  extraEnvVars:
    - name: LOG_LEVEL
      value: error

Alternatively, you can use a ConfigMap or a Secret with the environment variables. To do so, use the extraEnvVarsCM or the extraEnvVarsSecret values.

⁠Sidecars

If additional containers are needed in the same pod as grafana-loki (such as additional metrics or logging exporters), they can be defined using the sidecars parameter inside each of the subsections: distributor, compactor, ingester, querier, queryFrontend and vulture.

sidecars:
- name: your-image-name
  image: your-image
  imagePullPolicy: Always
  ports:
  - name: portname
    containerPort: 1234

If these sidecars export extra ports, extra port definitions can be added using the service.extraPorts parameter (where available), as shown in the example below:

service:
  extraPorts:
  - name: extraPort
    port: 11311
    targetPort: 11311

If additional init containers are needed in the same pod, they can be defined using the initContainers parameter. Here is an example:

initContainers:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
        containerPort: 1234

Learn more about sidecar containers⁠ and init containers⁠.

⁠Pod affinity

This chart allows you to set your custom affinity using the affinity parameter. Find more information about Pod affinity in the kubernetes documentation⁠.

As an alternative, use one of the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common⁠ chart. To do so, set the podAffinityPreset, podAntiAffinityPreset, or nodeAffinityPreset parameters inside each of the subsections: distributor, compactor, ingester, querier, queryFrontend and vulture.

⁠External cache support

You may want to have Grafana Loki connect to an external Memcached rather than installing one inside your cluster. Typical reasons for this are to use a managed cache service, or to share a common cache server for all your applications. To achieve this, the chart allows you to specify credentials for an external database with the externalMemcached parameter⁠. You should also disable the Memcached installation with the memcached.enabled option. Here is an example:

memcached.enabled=false
externalMemcached.host=myexternalhost
externalMemcached.port=11211

⁠Backup and restore

To back up and restore Helm chart deployments on Kubernetes, you need to back up the persistent volumes from the source deployment and attach them to a new deployment using Velero⁠, a Kubernetes backup/restore tool. Find the instructions for using Velero in this guide⁠.

⁠Persistence

⁠Limitation

This chart does not function fully when using local filesystem as a persistence store. When using a local filesystem as a persistence store, querying will not be possible (or limited to the ingesters' in-memory caches). For a fully functional deployment of this helm chart, an object storage backend is required.

⁠Data

The Bitnami grafana-loki⁠ image stores the grafana-loki ingester data at the /bitnami path of the container. Persistent Volume Claims are used to keep the data across deployments.

⁠Parameters

⁠Global parameters

⁠Common parameters

⁠Common Grafana Loki Parameters

⁠Compactor Deployment Parameters

Note: the README for this chart is longer than the DockerHub length limit of 25000, so it has been trimmed. The full README can be found at https://github.com/bitnami/charts/blob/main/bitnami/grafana-loki/README.md⁠