Configuration

The configuration for the CrateDB Kubernetes Operator follows the 12 Factor Principles and uses environment variables. All environment variables are expected to use upper case letters and must be prefixed with CRATEDB_OPERATOR_.

BOOTSTRAP_TIMEOUT

When deploying a cluster, the operator will perform some bootstrap tasks as documented in the Concepts section. The operator will wait at most this many seconds until it considers the bootstrapping to have failed. Set to 0 to disable timeouts.

The default value is 1800 seconds.

CLOUD_PROVIDER

Some cloud providers require a specific setup for CrateDB nodes, due to the availability guarantees of the underlying infrastructure. For example, in AWS, a block storage used by CrateDB as a data partition is only available in one availability zone (AZ) of that corresponding AWS region. If all copies of some shard were located in the same AZ, an outage of that AZ would imply some data being unavailable in CrateDB.

To ensure CrateDB properly replicates shards to other nodes in different availability zones, one can make use of CrateDB’s routing allocation awareness. For example, deploying a cluster in AWS’ eu-central-1 region:

kind: CrateDB
spec:
  cluster:
    settings:
      cluster.routing.allocation.awareness.attributes: "zone"
      cluster.routing.allocation.awareness.force.zone.values: "eu-central-1a,eu-central-1b,eu-central-1c"

Allowed values:

• aws

• azure

Under the hood, the operator will pass a zone attribute to all CrateDB nodes. This attribute can also be defined explicitly or override the one set by the operator. To do this on a cluster level, set .spec.cluster.settings:

kind: CrateDB
spec:
  cluster:
    settings:
      node.attr.zone: "some-value"

To set or override the attribute on a node type level, set it in .spec.nodes.master.settings or .spec.nodes.data.*.settings.

CLUSTER_BACKUP_IMAGE

When enabling backups for a cluster, the operator deploys a Prometheus exporter to be scraped for backup metrics, and a Kubernetes CronJob that creates backups every defined interval. If WEBHOOK_URL and related credentials are specified, the backup CronJob will post backup creation events back to the webhook URL. This variable needs to point to a Docker image and tag to use it for the exporter and CronJob.

DEBUG_VOLUME_SIZE

The volume size for the PersistentVolume that is used as a storage location for Java heap dumps.

The default value is 256 GiB.

DEBUG_VOLUME_STORAGE_CLASS

The Kubernetes storage class name for the PersistentVolume that is used as a storage location for Java heap dumps.

The default value is crate-local.

IMAGE_PULL_SECRETS

A comma-separated list of Kubernetes image pull secrets. Each Kubernetes resource created by the operator will have all these secrets attached.

The default value is an empty list.

JMX_EXPORTER_VERSION

(Required)

CrateDB exports metrics via the JMX protocol. This is the version of the exporter to be used.

KUBECONFIG

If defined, it needs to point to a valid Kubernetes configuration file. Due to the underlying libraries, multiple paths, such as /path/to/kube.conf:/another/path.conf, are not allowed. For compatibility and ease of use, if CRATEDB_OPERATOR_KUBECONFIG is not defined, the operator will also look for the KUBECONFIG environment variable. Default is None and leads to “in-cluster” configuration.

LOG_LEVEL

The log level used for log messages emitted by the CrateDB Kubernetes Operator. Valid values are CRITICAL, ERROR, WARNING, INFO, or DEBUG.

The default value is INFO.

ROLLING_RESTART_TIMEOUT

A rolling cluster restart takes some time, depending on the cluster size, number of nodes, amount of data, etc. After some change operations, such as cluster upgrades, the operator will trigger a rolling cluster restart. The operator will wait at most this many seconds until it considers the rolling restart to have failed. Set to 0 to disable timeouts.

The default value is 3600 seconds.

SCALING_TIMEOUT

When scaling a cluster, the operator will sometimes need to deallocate some CrateDB nodes before turning them off. To ensure the operator keeps functioning on the resource, scaling operations will be aborted after this many seconds and will be considered to have failed. Set to 0 to disable timeouts.

The default value is 3600 seconds.

TESTING

During development or testing, some constraints enforced by the operator may be obstructive. One such example is the Kubernetes pod anti-affinity on all CrateDB pods, which guarantees that a single Kubernetes node failure doesn’t take down several CrateDB nodes. This makes deploying a CrateDB cluster that has explicit master nodes impossible on a 3-node Kubernetes cluster, because there would be 3 master + n data nodes.

Setting this to True will remove the constraint.

Danger

Do not set this variable when running the operator in production! It will impact the reliability of your CrateDB clusters!

The default value is False.

WEBHOOK_PASSWORD

Any webhook request submitted by the operator will include HTTP Basic Auth credentials. This is the password.

The default value is None.

WEBHOOK_URL

The operator can optionally be configured to submit HTTP POST requests to an API upon certain events (see Webhooks). For that to work, the WEBHOOK_PASSWORD, WEBHOOK_URL, and WEBHOOK_USERNAME need to be set.

The default value is None.

WEBHOOK_USERNAME

Any webhook request submitted by the operator will include HTTP Basic Auth credentials. This is the username.

The default value is None.

NO_DOWNTIME_STORAGE_EXPANSION

Whether to perform volume expansion operations without suspending the cluster. For this to work, it must be supported by the underlying infrastructure. At the time of writing, this works on Azure AKS and AWS EKS if using the CSI drivers.

By default, the operator will suspend the cluster while performing volume expansion, and resume it once the PVCs expand.

The default value is False.