Elasticsearch breaking changes

Breaking changes can impact your Elastic applications, potentially disrupting normal operations. Before you upgrade, carefully review the Elasticsearch breaking changes and take the necessary steps to mitigate any issues.

If you are migrating from a version prior to version 9.0, you must first upgrade to the last 8.x version available. To learn how to upgrade, check out Upgrade.

To learn how to upgrade, check out <uprade docs>.

Allocation

• Increase minimum threshold in shard balancer #115831
• Remove cluster.routing.allocation.disk.watermark.enable_for_single_data_node setting #114207
• Remove cluster state from /_cluster/reroute response #114231 (issue: #88978)

Analysis

• Snowball stemmers have been upgraded #114146
• The german2 stemmer is now an alias for the german snowball stemmer #113614
• The persian analyzer has stemmer by default #113482 (issue: #113050)
• The Korean dictionary for Nori has been updated #114124

Cluster Coordination

• Remove unsupported legacy value for discovery.type #112903

Highlighting

• Remove support for deprecated force_source highlighting parameter #116943

Indices APIs

• Apply more strict parsing of actions in bulk API #115923
• Remove deprecated local attribute from alias APIs #115393

Infra/REST API

• Output a consistent format when generating error json #90529 (issue: #89387)

Ingest Node

• Remove ecs option on user_agent processor #116077
• Remove ignored fallback option on GeoIP processor #116112

Mapping

• Remove support for type, fields, copy_to and boost in metadata field definition #116944

Search

• Remove legacy params from range query #116970

Snapshot/Restore

• Remove deprecated xpack.searchable.snapshot.allocate_on_rolling_restart setting #114202