How to Configure Data Plane Resilience

Starting in version 3.2, Kong Gateway can be configured to support configuring new data planes in the event of a control plane outage. This feature works by designating a backup node and allowing it read/write access to a data store. This backup node will automatically push valid Kong Gateway configurations to the data store. In the event of a control plane outage when a new node is created, it will pull the latest Kong Gateway configuration from the data store, configure itself, and start proxying requests.

This option is only recommended for customers who are have to adhere to strict availability SLAs, because it requires a larger maintenance load.

Amazon S3

GCP Cloud Storage

S3 object storage

Prerequisites

  • An Amazon S3 service and bucket.
  • Read/write credentials for the bucket.

Configuration

In this setup, you will need to designate one backup node. The backup node must have read/write access to the S3 compatible storage volume and the data plane nodes that are provisioned must have read access to the storage volume. This node is responsible for communicating the state of the Kong Gateway kong.conf configuration file from the control plane to the storage volume. Nodes are initialized with fallback configs via environment variables, including AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, and AWS_DEFAULT_REGION. A backup node should not be used to proxy traffic. A single backup node is sufficient for all deployments. For more information about the data that is set in the environment variables, review the AWS environment variable configuration documentation.

Using Docker Compose, you can configure the backup data plane:

  1. kong-exporter:
  2.     image: 'kong/kong-gateway:latest'
  3.     ports:
  4.       - '8000:8000'
  5.       - '8443:8443'
  6.     environment:
  7.       <<: *other-kong-envs
  8.       AWS_REGION: 'us-east-2'
  9.       AWS_ACCESS_KEY_ID: <access_key_write>
  10.       AWS_SECRET_ACCESS_KEY: <secret_access_key_write>
  11.       KONG_CLUSTER_FALLBACK_CONFIG_STORAGE: s3://test-bucket/test-prefix
  12.       KONG_CLUSTER_FALLBACK_CONFIG_EXPORT: "on"

This node is responsible for writing to the S3 bucket when it receives a new configuration. If the node version is 3.2.0.0, the key name should be test-prefix/3.2.0.0/config.json. Both the control plane and data plane can be configured to export configurations.

You can configure new data planes to load a configuration from a bucket if the control plane is unreachable using the following environment variables:

  1. kong-dp-importer:
  2.     image: 'kong/kong-gateway:latest'
  3.     ports:
  4.       - '8000:8000'
  5.       - '8443:8443'
  6.     environment:
  7.       <<: *other-kong-envs
  8.       AWS_REGION: 'us-east-2'
  9.       AWS_ACCESS_KEY_ID: <access_key_read>
  10.       AWS_SECRET_ACCESS_KEY: <secret_access_key_read>
  11.       KONG_CLUSTER_FALLBACK_CONFIG_STORAGE: s3://test-bucket/test-prefix
  12.       KONG_CLUSTER_FALLBACK_CONFIG_IMPORT: "on"

Prerequisites

  • A GCP cloud storage bucket
  • Read/write credentials for the bucket.

Configuration

In this setup you will need to designate one backup node. The backup node must have read/write access to the storage volume, and the data plane nodes supposed to be provisioned must have read access to the storage volume. This node is responsible for communicating the state of the Kong Gateway kong.conf configuration file from the control plane to the storage volume. A backup node should not be used to proxy traffic. A single backup node is sufficient for all deployments. Credentials are passed via the environment variable GCP_SERVICE_ACCOUNT. For more information about credentials review the GCP credentials documentation.

Using Docker Compose, configure the node:

  1. kong-dp-exporter:
  2.     image: 'kong/kong-gateway:latest'
  3.     ports:
  4.       - '8000:8000'
  5.       - '8443:8443'
  6.     environment:
  7.       <<: *other-kong-envs
  8.       KONG_CLUSTER_FALLBACK_CONFIG_STORAGE: gcs://test-bucket/
  9.       KONG_CLUSTER_FALLBACK_CONFIG_EXPORT: "on"
  10.       GCP_SERVICE_ACCOUNT: <GCP_JSON_STRING_WRITE>

This node will ship backup configurations to the GCP bucket when it receives a new configuration. If the version is 3.2.0.0, the key name should be test-prefix/3.2.0.0/config.json.

A new data plane can be configured to load a configuration from GCP bucket if the control plane is not reachable using the following environment variables:

  1.   kong-dp-importer:
  2.     image: 'kong/kong-gateway:latest'
  3.     ports:
  4.       - '8000:8000'
  5.       - '8443:8443'
  6.     environment:
  7.       <<: *other-kong-envs
  8.       KONG_CLUSTER_FALLBACK_CONFIG_STORAGE: gcs://test-bucket/
  9.       KONG_CLUSTER_FALLBACK_CONFIG_IMPORT: "on"
  10.       GCP_SERVICE_ACCOUNT: <GCP_JSON_STRING_READ>

Non-AWS S3 compatible object storage can be configured. The process is similar to the AWS S3 process, but requires an additional parameter AWS_CONFIG_STORAGE_ENDPOINT, which should be set to the endpoint of your object storage provider.

The example below uses MinIO to demonstrate configuring a backup node:

  1.   kong-exporter:
  2.     image: 'kong/kong-gateway:latest'
  3.     ports:
  4.       - '8000:8000'
  5.       - '8443:8443'
  6.     environment:
  7.       <<: *other-kong-envs
  8.       AWS_REGION: 'us-east-2'
  9.       AWS_ACCESS_KEY_ID: <access_key_write>
  10.       AWS_SECRET_ACCESS_KEY: <secret_access_key_write>
  11.       KONG_CLUSTER_FALLBACK_CONFIG_EXPORT: "on"
  12.       AWS_CONFIG_STORAGE_ENDPOINT: http://minio:9000/

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