[DOC] Segment Replication + Remote Storage

[mch2]

What do you want to do?

• Request a change to existing documentation
• Add new documentation
• Report a technical problem with the documentation
• Other

Tell us about your request. Provide a summary of the request and all versions that are affected.
Segment Replication and Remote storage (experimental) have their own sets of documentation. We would like to include new documentation covering the integration of these two features (for release in 2.9), where segment replication uses a remote store to copy out segments to replicas. The meta issue & design proposal is here - opensearch-project/OpenSearch#4448

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
Test plan - opensearch-project/OpenSearch#8109 where we will include results to include in docs.

There are no new APIs for this feature, however we will need to document the performance implications along with configuration options.

Configuration:
If remote store is enabled, all indices will internally use segment replication to copy to replicas. There will be no index level override option that is provide with node-node segment replication.

[Naarcha-AWS]

Status is currently in RED. Will update on July 5 with a better idea of if this will make 2.9.

[hdhalter]

This is moving to 2.10 as reported in the project call on 6/6.

[dreamer-89]

@Naarcha-AWS @hdhalter : I see some additional documentation changes/addition for 2.10.0 release. Please also include these changes (Issue #5011). Let know in you need more details to open the doc PR.