[DOC] Search Only strict Cluster Routing setting

[vinaykpud]

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We are adding a new cluster routing setting cluster.routing.search_replica.strict for search replicas. This setting accepts boolean values.
By default value of this will be true and its applicable only if the search replicas exist for an index ie index.number_of_search_replicas for an index is greater than 0.
If the search replicas exists for an index by default _search requests will be routed to search replicas. But when we have search replicas value of cluster.routing.search_replica.strict setting can made false so that _search requests can land on any available shard.

Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.
3.0 onwards

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Reader Writer separation meta and issues: opensearch-project/OpenSearch#15306
PR: opensearch-project/OpenSearch#17803

[opensearch-ci-bot]

Hi @vinaykpud
,

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Thank you!

[vinaykpud]

cluster.routing.search_replica.strict (Boolean):
Controls how search requests are routed when search replica shards exist for an index (i.e., when index.number_of_search_replicas is greater than 0). This setting is only applicable when search replicas are configured for an index.

• When set to true, all _search requests for such indices are routed only to search replica shards.
• When set to false, _search requests can be routed to any available shard, including primary and non-search replicas.

If not set, default is true