[AUTO] Add release notes for 3.6.0 Draft 2

[opensearch-ci-bot]

Add release notes for 3.6.0

Borderline Calls

• Add support of IndexWarmer for replica shards with segment replication enabled #20650 (IndexWarmer for replicas): Categorized as Enhancement rather than Feature since index warming already exists; this extends it to replica shards with segment replication.
• Add indexer interface for shard interaction with underlying engines #20675 (Indexer interface): Categorized as Enhancement. It's an internal abstraction refactor but introduces a new public interface that plugin authors may use, so included.
• [Backport 3.6] Updated MMapDirectory to use ReadAdviseByContext rather than default readadvise of Lucene #21062 (MMapDirectory ReadAdviseByContext): Categorized as Enhancement. Backport PR but contains a meaningful user-facing performance change.
• Make Telemetry Tags Immutable #20788 (Immutable Tags): Categorized as Enhancement. Internal refactor but changes public API behavior (addTag now returns new instance).
• feat(hunspell): Add ref_path support for package-based dictionary loa… #20840 (Hunspell ref_path): Categorized as Enhancement. Labeled skip-diff-analyzer but introduces new user-facing functionality (ref_path parameter).
• Move Randomness from server to lib/common #20570 (Move Randomness): Categorized as Bug Fix per its "bug" label, though it's arguably maintenance. The user-facing impact is reducing FIPS installer size.
• Use env variable (OPENSEARCH_FIPS_MODE) to enable opensearch to run in FIPS enforced mode instead of checking for existence of bcFIPS jars #20625 (FIPS env var): Categorized as Bug Fix. Labeled backport 3.5 but changes user-facing configuration behavior.
• Harden detection of HTTP/3 support by ensuring Quic native libraries are available for the target platform #20680 (HTTP/3 Quic detection): Categorized as Bug Fix. Labeled backport 3.5 but fixes a real platform compatibility issue.
• Ensure that transient ThreadContext headers with propagators survive restore #20854 (ThreadContext headers): Included despite skip-diff-analyzer label because it fixes a real user-facing tracing bug.
• feat(hunspell): Add ref_path support for package-based dictionary loa… #20840 (Hunspell ref_path): Included despite skip-diff-analyzer label because it adds new user-facing functionality.
• Introducing indexing & deletion strategy planner interfaces #20585 (Strategy planner interfaces): Excluded as internal refactoring with no direct user-facing change; foundational for future work.
• Disable concurrent search for filter duplicates in significant_text #20857/Revert "Disable concurrent search for filter duplicates" #20915 (Disable/revert concurrent search for significant_text): Excluded as the revert cancels the original change.
• Remove incorrect entries re-added by 3154811 #20853 (Remove incorrect changelog entries): Excluded as release machinery.
• [AUTOCUT] Gradle Check Flaky Test Report for OpenSearchTestBasePluginFuncTest #20955 (Fix flaky test): Excluded as test-only.
• Search Benchmark testing #83 (Add bwc version): Excluded as release machinery.
• [GRPC] Add accessUnixDomainSocket permission for transport-grpc #20463 (GRPC permission initial): Excluded; [GRPC] Add accessUnixDomainSocket permission for transport-grpc #20649 is the follow-up that landed the actual fix.
• [GRPC] Handle ShardSearchFailure properly #20641 (GRPC ShardSearchFailure): Excluded as internal proto fix with no user-facing config/behavior change.
• Fix stream transport TLS cert hot-reload by using live SSLContext fro… #20734 (stream transport TLS): Included separately from Flight transport TLS cert hot-reload #20700 (Flight TLS) as they fix different transport layers.
• Flight transport TLS cert hot-reload #20700/Fix stream transport TLS cert hot-reload by using live SSLContext fro… #20734 (TLS hot-reload): Categorized as Bug Fix despite backport labels; they fix real cert reload failures.

[github-actions]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 No relevant tests

🔒 No security concerns identified

✅ No TODO sections

🔀 No multiple PR themes

⚡ Recommended focus areas for review Missing Entry The old version included a bump for com.netflix.nebula:gradle-info-plugin to 16.2.1 (PR #20825), but this entry was removed in the new version without any mention in the PR description or borderline calls. Verify whether this was intentionally excluded. * Bump Apache Lucene from 10.3.2 to 10.4.0 ([#20735](https://github.com/opensearch-project/OpenSearch/pull/20735)) * Update Netty to 4.2.12.Final ([#20586](https://github.com/opensearch-project/OpenSearch/pull/20586)), ([#20997](https://github.com/opensearch-project/OpenSearch/pull/20997)), ([#20998](https://github.com/opensearch-project/OpenSearch/pull/20998)) * Update Jackson to 2.21.2 ([#20989](https://github.com/opensearch-project/OpenSearch/pull/20989)) * Bump OpenTelemetry to 1.60.1 and OpenTelemetry Semconv to 1.40.0 ([#20737](https://github.com/opensearch-project/OpenSearch/pull/20737)), ([#20797](https://github.com/opensearch-project/OpenSearch/pull/20797)) * Bump Project Reactor to 3.8.4 and Reactor Netty to 1.3.4 ([#20589](https://github.com/opensearch-project/OpenSearch/pull/20589)), ([#20834](https://github.com/opensearch-project/OpenSearch/pull/20834)) * Bump `ch.qos.logback:logback-classic` to 1.5.32 and `logback-core` to 1.5.27 ([#20525](https://github.com/opensearch-project/OpenSearch/pull/20525)), ([#20761](https://github.com/opensearch-project/OpenSearch/pull/20761)) * Bump `com.nimbusds:nimbus-jose-jwt` from 10.7 to 10.8 ([#20715](https://github.com/opensearch-project/OpenSearch/pull/20715)) * Bump `com.sun.xml.bind:jaxb-impl` from 4.0.6 to 4.0.7 ([#20886](https://github.com/opensearch-project/OpenSearch/pull/20886)) * Bump `com.netflix.nebula.ospackage-base` from 12.2.0 to 12.3.0 ([#20799](https://github.com/opensearch-project/OpenSearch/pull/20799)) * Bump `org.apache.commons:commons-text` from 1.14.0 to 1.15.0 ([#20576](https://github.com/opensearch-project/OpenSearch/pull/20576)) * Bump `org.jline:jline` from 3.30.6 to 4.0.0 ([#20800](https://github.com/opensearch-project/OpenSearch/pull/20800)) * Bump `org.jruby.jcodings:jcodings` from 1.0.63 to 1.0.64 ([#20713](https://github.com/opensearch-project/OpenSearch/pull/20713)) * Bump `org.jruby.joni:joni` from 2.2.3 to 2.2.7 ([#20714](https://github.com/opensearch-project/OpenSearch/pull/20714)), ([#20759](https://github.com/opensearch-project/OpenSearch/pull/20759)) * Bump `org.tukaani:xz` from 1.11 to 1.12 ([#20760](https://github.com/opensearch-project/OpenSearch/pull/20760)) * Bump shadow-gradle-plugin from 8.3.9 to 9.3.1 ([#20569](https://github.com/opensearch-project/OpenSearch/pull/20569)) Misplaced Entry The entry for mapper_settings support (#20722) was moved from the Enhancements section to the Features section. Verify this categorization is intentional, as it appears to be an enhancement to pull-based ingestion rather than a new feature. * Add mapper_settings support and field_mapping mapper type for pull-based ingestion ([#20722](https://github.com/opensearch-project/OpenSearch/pull/20722)) Misplaced Entry The entry for ReadAdviseByContext for MMapDirectory (#21062) was moved from Bug Fixes to Enhancements. The PR description categorizes it as an Enhancement, but the old notes had it under Bug Fixes. Confirm the correct section placement. * Use `ReadAdviseByContext` for MMapDirectory instead of Lucene default read advise ([#21062](https://github.com/opensearch-project/OpenSearch/pull/21062))

[github-actions]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Fix inconsistent multi-PR link formatting The formatting for multiple PR links is inconsistent with the rest of the file. Other entries with multiple PRs use a comma-separated list within a single set of parentheses, but this line wraps each additional PR in its own parentheses preceded by a comma. This should be standardized to match the original format used by other multi-PR entries. release-notes/opensearch.release-notes-3.6.0.md [73] -* Update Netty to 4.2.12.Final ([#20586](https://github.com/opensearch-project/OpenSearch/pull/20586)), ([#20997](https://github.com/opensearch-project/OpenSearch/pull/20997)), ([#20998](https://github.com/opensearch-project/OpenSearch/pull/20998)) +* Update Netty to 4.2.12.Final ([#20586](https://github.com/opensearch-project/OpenSearch/pull/20586), [#20997](https://github.com/opensearch-project/OpenSearch/pull/20997), [#20998](https://github.com/opensearch-project/OpenSearch/pull/20998)) Suggestion importance[1-10]: 5 __ Why: The Netty entry uses ), ( between PR links while other multi-PR entries like OpenTelemetry, Project Reactor, and logback use , within a single set of parentheses. This is a valid consistency fix for the release notes formatting.	Low
	Verify correct section categorization for entry This entry appears under "Enhancements" but the removed lines show it was previously listed under "Bug Fixes". Moving it to Enhancements changes the categorization of this change, which may be misleading to users reading the release notes. Verify the correct section for this entry. release-notes/opensearch.release-notes-3.6.0.md [34] +* Use `ReadAdviseByContext` for MMapDirectory instead of Lucene default read advise ([#21062](https://github.com/opensearch-project/OpenSearch/pull/21062)) - Suggestion importance[1-10]: 3 __ Why: The suggestion correctly identifies that the ReadAdviseByContext entry moved from "Bug Fixes" to "Enhancements", but since the improved_code is identical to existing_code, this is only a verification request rather than a concrete fix, limiting its score.	Low

[peterzhuamazon]

@andrross @jainankitk

This is the second PR on OS core release notes, that have changes right after

• [AUTO] Add release notes for 3.6.0 #21045

I think mostly it is just rotating a few entries.

Let me know if these changes are legit.

Thanks.