Configure allocator affinity

One of the benefits of the ECE platform is its robust deployment instance distribution logic that maximizes the utilization of the underlying resources you deploy the Elastic Stack on. In ECE 2.4 and later, you can customize how Elastic Stack deployments get distributed across the available set of allocators in your ECE installation, which is known as allocator affinity.

Configuring allocator affinity is an optional post-installation task that changes the behavior of Elastic Cloud Enterprise. If you do not explicitly set an affinity strategy, all instances use the fill-anti-affinity strategy by default.

To follow these steps, you must be familiar with using the ECE RESTful API. The API examples in this topic use HTTPS, which requires that you have a TLS certificate already installed. For testing purposes only, you can specify the -k option to turn off certificate verification, as shown in our examples, or use HTTP over port 12400 until you get your TLS certificate sorted out.

The following distribution strategies to configure allocator affinity are available:

To check how allocator affinity is currently configured:

curl -X GET -u admin:PASSWORD -k https://COORDINATOR_HOST:12443/api/v1/platform/configuration/store/constructor
{
  "errors": [{
    "code": "platform.config.store.not_found",
    "message": "Config option [constructor] could not be found"
  }]
}

If a configuration option cannot be found, the default fill-anti-affinity strategy is being used.

To set allocator affinity to the distribute-anti-affinity strategy:

curl -X POST -u admin:PASSWORD -k https://COORDINATOR_HOST:12443/api/v1/platform/configuration/store/constructor -H 'Content-Type: application/json' -d '{ "value": "{ \"allocator_prioritization\": \"distribute-anti-affinity\" }" }'
{
  "changed": false,
  "name": "constructor",
  "value": "{ \"allocator_prioritization\": \"distribute-anti-affinity\" }"
}

To update allocator affinity to the distribute strategy:

curl -X PUT -u admin:PASSWORD -k https://COORDINATOR_HOST:12443/api/v1/platform/configuration/store/constructor -H 'Content-Type: application/json' -d '{ "value": "{ \"allocator_prioritization\": \"distribute\" }" }'
{
  "changed": true,
  "name": "constructor",
  "value": "{ \"allocator_prioritization\": \"distribute\" }"
}

To change allocator affinity back to the default behavior:

curl -X DELETE -u admin:PASSWORD -k https://COORDINATOR_HOST:12443/api/v1/platform/configuration/store/constructor
{

}