Kong is an open source Microservice API gateway and platform designed for managing microservices requests of high-availability, fault-tolerance, and distributed systems.

Overview of Kong

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_NAME/REPOSITORY_NAME/kong

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository.

Introduction

This chart bootstraps a kong deployment on a Kubernetes cluster using the Helm package manager. It also includes the kong-ingress-controller container for managing Ingress resources using Kong.

Extra functionalities beyond the Kong core are extended through plugins. Kong is built on top of reliable technologies like NGINX and provides an easy-to-use RESTful API to operate and configure the system.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters.

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/kong

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

These commands deploy kong on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

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.

Prometheus metrics

This chart can be integrated with Prometheus by setting metrics.enabled to true. This will enable Kong native prometheus port in all pods and a metrics service, which can be configured under the metrics.service section. This metrics service will 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.

Database backend

The Bitnami Kong chart allows setting two database backends: PostgreSQL or Cassandra. For each option, there are two extra possibilities: deploy a sub-chart with the database installation or use an existing one. The list below details the different options (replace the placeholders specified between UNDERSCORES):

• Deploy the PostgreSQL sub-chart (default)

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/kong

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

• Use an external PostgreSQL database

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/kong \
    --set postgresql.enabled=false \
    --set postgresql.external.host=_HOST_OF_YOUR_POSTGRESQL_INSTALLATION_ \
    --set postgresql.external.password=_PASSWORD_OF_YOUR_POSTGRESQL_INSTALLATION_ \
    --set postgresql.external.user=_USER_OF_YOUR_POSTGRESQL_INSTALLATION_

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

• Deploy the Cassandra sub-chart

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/kong \
    --set database=cassandra \
    --set postgresql.enabled=false \
    --set cassandra.enabled=true

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

• Use an existing Cassandra installation

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/kong \
    --set database=cassandra \
    --set postgresql.enabled=false \
    --set cassandra.enabled=false \
    --set cassandra.external.hosts[0]=_CONTACT_POINT_0_OF_YOUR_CASSANDRA_CLUSTER_ \
    --set cassandra.external.hosts[1]=_CONTACT_POINT_1_OF_YOUR_CASSANDRA_CLUSTER_ \
    ...
    --set cassandra.external.user=_USER_OF_YOUR_CASSANDRA_INSTALLATION_ \
    --set cassandra.external.password=_PASSWORD_OF_YOUR_CASSANDRA_INSTALLATION_

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

DB-less

Kong 1.1 added the capability to run Kong without a database, using only in-memory storage for entities: we call this DB-less mode. When running Kong DB-less, the configuration of entities is done in a second configuration file, in YAML or JSON, using declarative configuration (ref. Link). As is said in step 4 of kong official docker installation, just add the env variable “KONG_DATABASE=off”.

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.

How to enable it

1. Set database value with any value other than “postgresql” or “cassandra”. For example database: "off"
2. Use kong.extraEnvVars value to set the KONG_DATABASE environment variable:

kong.extraEnvVars:
- name: KONG_DATABASE
  value: "off"

Sidecars and Init Containers

If you have a need for additional containers to run within the same pod as Kong (e.g. an additional metrics or logging exporter), you can do so via the sidecars config parameter. Simply define your container according to the Kubernetes container spec.

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

Similarly, you can add extra init containers using the initContainers parameter.

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

Adding extra environment variables

In case you want to add extra environment variables (useful for advanced operations like custom init scripts), you can use the kong.extraEnvVars property.

kong:
  extraEnvVars:
    - name: KONG_LOG_LEVEL
      value: error

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

The Kong Ingress Controller and the Kong Migration job also allow this kind of configuration via the ingressController.extraEnvVars, ingressController.extraEnvVarsCM, ingressController.extraEnvVarsSecret, migration.extraEnvVars, migration.extraEnvVarsCM and migration.extraEnvVarsSecret values.

Using custom init scripts

For advanced operations, the Bitnami Kong charts allows using custom init scripts that will be mounted in /docker-entrypoint.init-db. You can use a ConfigMap or a Secret (in case of sensitive data) for mounting these extra scripts. Then use the kong.initScriptsCM and kong.initScriptsSecret values.

elasticsearch.hosts[0]=elasticsearch-host
elasticsearch.port=9200
initScriptsCM=special-scripts
initScriptsSecret=special-scripts-sensitive

Deploying extra resources

There are cases where you may want to deploy extra objects, such as KongPlugins, KongConsumers, amongst others. For covering this case, the chart allows adding the full specification of other objects using the extraDeploy parameter. The following example would activate a plugin at deployment time.

## Extra objects to deploy (value evaluated as a template)
##
extraDeploy:
  - |
    apiVersion: configuration.konghq.com/v1
    kind: KongPlugin
    metadata:
      name: {{ include "common.names.fullname" . }}-plugin-correlation
      namespace: {{ .Release.Namespace }}
      labels: {{- include "common.labels.standard" ( dict "customLabels" .Values.commonLabels "context" $ ) | nindent 6 }}
    config:
      header_name: my-request-id
    plugin: correlation-id

Setting Pod’s affinity

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

As an alternative, you can use 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.

Parameters

Global parameters

Common parameters

Kong common parameters

Kong deployment / daemonset parameters

Kong Container Parameters

Traffic Exposure Parameters

Kong Ingress Controller Container Parameters

Kong Migration job Parameters

PostgreSQL Parameters

Cassandra Parameters

Metrics Parameters

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

helm install my-release \
  --set service.exposeAdmin=true oci://REGISTRY_NAME/REPOSITORY_NAME/kong

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

The above command exposes the Kong admin ports inside the Kong service.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

helm install my-release -f values.yaml oci://REGISTRY_NAME/REPOSITORY_NAME/kong

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts. Tip: You can use the default values.yaml

Troubleshooting

Find more information about how to deal with common errors related to Bitnami’s Helm charts in this troubleshooting guide.

Upgrading

To 15.1.0

This version introduces image verification for security purposes. To disable it, set global.security.allowInsecureImages to true. More details at GitHub issue.

It’s necessary to specify the existing passwords while performing a upgrade to ensure the secrets are not updated with invalid randomly generated passwords. Remember to specify the existing values of the postgresql.postgresqlPassword or cassandra.password parameters when upgrading the chart:

helm upgrade my-release oci://REGISTRY_NAME/REPOSITORY_NAME/kong \
    --set database=postgresql
    --set postgresql.enabled=true
    --set
    --set postgresql.postgresqlPassword=[POSTGRESQL_PASSWORD]

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts. Note: you need to substitute the placeholders [POSTGRESQL_PASSWORD] with the values obtained from instructions in the installation notes.

To 15.0.0

This major updates the PostgreSQL version from 14.x.x to 17.x.x. Instead of overwritting it in this chart values, it will automatically use the version defined in the postgresql subchart.

To 14.0.0

This major updates the PostgreSQL subchart to its newest major, 16.0.0, which uses PostgreSQL 17.x. Follow the official instructions to upgrade to 17.x.

To 13.0.0

This major updates the Cassandra subchart to its newest major, 12.0.0. Here you can find more information about the changes introduced in that version.

To 12.0.0

This major bump changes the following security defaults:

• runAsGroup is changed from 0 to 1001
• readOnlyRootFilesystem is set to true
• resourcesPreset is changed from none to the minimum size working in our test suites (NOTE: resourcesPreset is not meant for production usage, but resources adapted to your use case).
• global.compatibility.openshift.adaptSecurityContext is changed from disabled to auto.

This could potentially break any customization or init scripts used in your deployment. If this is the case, change the default values to the previous ones.

To 11.0.0

This major release bumps the PostgreSQL chart version to 14.x.x; no major issues are expected during the upgrade.

To 10.0.0

This major updates the PostgreSQL subchart to its newest major, 13.0.0. Here you can find more information about the changes introduced in that version.

To 9.0.0

This major updates the Cassandra subchart to its newest major, 10.0.0. Here you can find more information about the changes introduced in that version.

To 8.0.0

This major updates the PostgreSQL subchart to its newest major, 12.0.0. Here you can find more information about the changes introduced in that version.

To 6.0.0

The postgresql sub-chart was upgraded to 11.x.x. Several values of the sub-chart were changed, so please check the upgrade notes.

No issues are expected during the upgrade.

To 5.0.0

The cassandra sub-chart was upgraded to 9.x.x. Several values of the sub-chart were changed, so please check the upgrade notes.

No issues are expected during the upgrade.

To 3.1.0

Kong Ingress Controller version was bumped to new major version, 1.x.x. The associated CRDs were updated accordingly.

To 3.0.0

On November 13, 2020, Helm v2 support was formally finished, this major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

What changes were introduced in this major version?

• Previous versions of this Helm Chart use apiVersion: v1 (installable by both Helm 2 and 3), this Helm Chart was updated to apiVersion: v2 (installable by Helm 3 only). Here you can find more information about the apiVersion field.
• Move dependency information from the requirements.yaml to the Chart.yaml
• After running helm dependency update, a Chart.lock file is generated containing the same structure used in the previous requirements.lock
• The different fields present in the Chart.yaml file has been ordered alphabetically in a homogeneous way for all the Bitnami Helm Charts
• This chart depends on the PostgreSQL 10 instead of PostgreSQL 9. Apart from the same changes that are described in this section, there are also other major changes due to the master/slave nomenclature was replaced by primary/readReplica. Here you can find more information about the changes introduced.

Considerations when upgrading to this version

• If you want to upgrade to this version using Helm v2, this scenario is not supported as this version doesn’t support Helm v2 anymore
• If you installed the previous version with Helm v2 and wants to upgrade to this version with Helm v3, please refer to the official Helm documentation about migrating from Helm v2 to v3
• If you want to upgrade to this version from a previous one installed with Helm v3, it should be done reusing the PVC used to hold the PostgreSQL data on your previous release. To do so, follow the instructions below (the following example assumes that the release name is kong):

NOTE: Please, create a backup of your database before running any of those actions.

Export secrets and required values to update

export POSTGRESQL_PASSWORD=$(kubectl get secret --namespace default kong-postgresql -o jsonpath="{.data.password}" | base64 -d)
export POSTGRESQL_PVC=$(kubectl get pvc -l app.kubernetes.io/instance=kong,app.kubernetes.io/name=postgresql,role=master -o jsonpath="{.items[0].metadata.name}")

Delete statefulsets

Delete PostgreSQL statefulset. Notice the option --cascade=false:

kubectl delete statefulsets.apps kong-postgresql --cascade=false

Upgrade the chart release

helm upgrade kong oci://REGISTRY_NAME/REPOSITORY_NAME/kong \
    --set postgresql.postgresqlPassword=$POSTGRESQL_PASSWORD \
    --set postgresql.persistence.existingClaim=$POSTGRESQL_PVC

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

Force new statefulset to create a new pod for postgresql

kubectl delete pod kong-postgresql-0

Finally, you should see the lines below in MariaDB container logs:

$ kubectl logs $(kubectl get pods -l app.kubernetes.io/instance=postgresql,app.kubernetes.io/name=postgresql,role=primary -o jsonpath="{.items[0].metadata.name}")
...
postgresql 08:05:12.59 INFO  ==> Deploying PostgreSQL with persisted data...
...

Useful links

• https://techdocs.broadcom.com/us/en/vmware-tanzu/application-catalog/tanzu-application-catalog/services/tac-doc/apps-tutorials-resolve-helm2-helm3-post-migration-issues-index.html
• https://helm.sh/docs/topics/v2_v3_migration/
• https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/

To 4.0.0

This major updates the Cassandra subchart to its newest major, 4.0.0. Here you can find more information about the changes introduced in those versions.

To 2.0.0

PostgreSQL and Cassandra dependencies versions were bumped to new major versions, 9.x.x and 6.x.x respectively. Both of these include breaking changes and hence backwards compatibility is no longer guaranteed.

In order to properly migrate your data to this new version:

• If you were using PostgreSQL as your database, please refer to the PostgreSQL Upgrade Notes.

• If you were using Cassandra as your database, please refer to the Cassandra Upgrade Notes.

License

Copyright © 2025 Broadcom. The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.