Serverless filtering create from

[seanzatzdev]

Some index settings are not available in Serverless, however, currently the /_create_from API does not work correctly, because it tries to copy some user-unsettable settings, e.g.

illegal_argument_exception: Settings [index.routing.allocation.include._tier_preference,index.number_of_replicas,index.number_of_shards] are not available when running in serverless mode

This PR fixes this for Serverless so the API can be used there:

POST _create_from/source/dest-index
{
    "acknowledged": true,
    "shards_acknowledged": true,
    "index": "dest-index"
}

I've got a follow up PR in the serverless repo that adds tests for this logic on serverless mode: https://github.com/elastic/elasticsearch-serverless/pull/4812

[Copilot]

Pull Request Overview

This PR fixes the /_create_from API in Serverless mode by filtering out settings that are not available in Serverless environments. Previously, the API attempted to copy user-unsettable settings like index.routing.allocation.include._tier_preference, index.number_of_replicas, and index.number_of_shards, causing failures. The fix adds logic to skip settings that are not serverless-public when running in serverless mode.

Key changes:

• Added serverless mode detection using DiscoveryNode.isStateless()
• Implemented filtering to exclude non-serverless-public settings when copying from source index

---

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[elasticsearchmachine]

Hi @seanzatzdev, I've created a changelog YAML for you.

[elasticsearchmachine]

Pinging @elastic/es-data-management (Team:Data Management)

[lukewhiting]

LGTM 👍🏻

[elasticsearchmachine]

💔 Backport failed

Status	Branch	Result
✅	9.2
❌	8.19	Commit could not be cherrypicked due to conflicts
❌	9.1	Commit could not be cherrypicked due to conflicts

You can use sqren/backport to manually backport by running backport --upstream elastic/elasticsearch --pr 137850

[seanzatzdev]

My first time using the backport label, seem to have missed those failures... Going to resolve this now

[seanzatzdev]

💔 Some backports could not be created

Status	Branch	Result
✅	9.1
❌	8.19	An unhandled error occurred. Please see the logs for details

Manual backport

To create the backport manually run:

backport --pr 137850

Questions ?

Please refer to the Backport tool documentation

[seanzatzdev]

💚 All backports created successfully

Status	Branch	Result
✅	8.19

Questions ?

Please refer to the Backport tool documentation