[BUG] Remote store clusters: Unable to update index.routing.allocation.total_primary_shards_per_node setting

[pandeydivyansh1803]

Describe the bug

When attempting to update the index.routing.allocation.total_primary_shards_per_node setting for an existing index in a remote store enabled cluster, an error is encountered stating that this setting can only be used with remote store enabled clusters, despite the cluster actually being remote store enabled.

Related component

No response

To Reproduce

1. Set up a remote store enabled OpenSearch cluster
2. Create a new index using the Create Index API
3. Attempt to update the index.routing.allocation.total_primary_shards_per_node setting for the created index using the Update Index Settings API

Expected behavior

The setting should be successfully updated for the index in the remote store enabled cluster.

Additional Details

Additional Notes:

• The error suggests that the system is not correctly recognizing that the cluster is remote store enabled when updating this specific setting.
• This issue only occurs when updating the setting for an existing index. If the setting is specified during index creation, it works as expected.