es-operator

Elasticsearch Operator

This is an operator for running Elasticsearch in Kubernetes with focus on operational aspects, like safe draining and offering auto-scaling capabilities for Elasticsearch data nodes, rather than just abstracting manifest definitions.

License

Starting with v0.1.3 the ES-Operator is dual-licensed under MIT and Apache-2.0 license. You can choose between one of them if you use this work.

SPDX-License-Identifier: MIT OR Apache-2.0

Compatibility

The ES-Operator has been tested with Elasticsearch 8.x and 9.x. Previously, we have also tested ES-Operator with Elasticsearch 6.x and 7.x, and while they still may be working, please consider support for these versions to be dropped.

How it works

The operator works by managing custom resources called ElasticsearchDataSets (EDS). They are basically a thin wrapper around StatefulSets. One EDS represents a common group of Elasticsearch data nodes. When applying an EDS manifest the operator will create and manage a corresponding StatefulSet.

Do not operate manually on the StatefulSet. The operator is supposed to own this resource on your behalf.

Key features

• It can scale in two dimensions, shards per node and number of replicas for the indices on that dataset.
• It works within scaling dimensions known to and long-term tested by teams in Zalando.
• Target CPU ratio is a safe and well-known metric to scale on in order to avoid latency spikes caused by Garbage Collection.
• In case of emergency, manual scaling is possible by disabling the auto-scaling feature.

Getting Started

For a quick tutorial how to deploy the ES Operator look at our Getting Started Guide.

Custom Resource

Full Example

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Custom resource properties

Key	Description	Type
spec.replicas	Initial size of the StatefulSet. If auto-scaling is disabled, this is your desired cluster size.	Int
spec.excludeSystemIndices	Enable or disable inclusion of system indices like '.kibana' when calculating shard-per-node ratio and scaling index replica counts. Those are usually managed by Elasticsearch internally. Default is false for backwards compatibility	Boolean
spec.skipDraining	Allows the ES Operator to terminate an Elasticsearch node without re-allocating its data. This is useful for persistent disk setups, like EBS volumes. Beware that the ES Operator does not verify that you have more than one copy of your indices and therefore wouldn't protect you from potential data loss. (default=false)	Boolean
spec.scaling.enabled	Enable or disable auto-scaling. May be necessary to enforce manual scaling.	Boolean
spec.scaling.minReplicas	Minimum Pod replicas. Lower bound (inclusive) when scaling down.	Int
spec.scaling.maxReplicas	Maximum Pod replicas. Upper bound (inclusive) when scaling up.	Int
spec.scaling.minIndexReplicas	Minimum index replicas. Lower bound (inclusive) when reducing index copies. (reminder: total copies is replicas+1 in Elasticsearch)	Int
spec.scaling.maxIndexReplicas	Maximum index replicas. Upper bound (inclusive) when increasing index copies.	Int
spec.scaling.minShardsPerNode	Minimum shard per node ratio. When reached, scaling up also requires adding more index replicas.	Int
spec.scaling.maxShardsPerNode	Maximum shard per node ratio. Boundary for scaling down.	Int
spec.scaling.scaleUpCPUBoundary	(Median) CPU consumption/request ratio to consistently exceed in order to trigger scale up.	Int
spec.scaling.scaleUpThresholdDurationSeconds	Duration in seconds required to meet the scale-up criteria before scaling.	Int
spec.scaling.scaleUpCooldownSeconds	Minimum duration in seconds between two scale up operations.	Int
spec.scaling.scaleDownCPUBoundary	(Median) CPU consumption/request ratio to consistently fall below in order to trigger scale down.	Int
spec.scaling.scaleDownThresholdDurationSeconds	Duration in seconds required to meet the scale-down criteria before scaling.	Int
spec.scaling.scaleDownCooldownSeconds	Minimum duration in seconds between two scale-down operations.	Int
spec.scaling.diskUsagePercentScaledownWatermark	If disk usage on one of the nodes exceeds this threshold, scaling down will be prevented.	Float
spec.experimental.draining.maxRetries	MaxRetries specifies the maximum number of attempts to drain a node.	Int
spec.experimental.draining.maximumWaitTimeDurationSeconds	MaximumWaitTimeDurationSeconds specifies the maximum wait time in seconds between retry attempts after a failed node drain.	Int
spec.experimental.draining.minimumWaitTimeDurationSeconds	MMinimumWaitTimeDurationSeconds specifies the minimum wait time in seconds between retry attempts after a failed node drain.	Int
status.lastScaleUpStarted	Timestamp of start of last scale-up activity	Timestamp
status.lastScaleUpEnded	Timestamp of end of last scale-up activity	Timestamp
status.lastScaleDownStarted	Timestamp of start of last scale-down activity	Timestamp
status.lastScaleDownEnded	Timestamp of end of last scale-down activity