In order for a data item to be registered and used successfully within the server's data store, you need to make sure that the
path (for file shares) or connection string (for databases) is accessible to every server node in the site. This can be
done by invoking the Validate Data Item operation on the JSON object representing the data store.
Validating a data item does not automatically register it for you. You need to explicitly register your data item
by invoking the Register Data Item operation.
http://server:port/arcgis/admin/data/validateItem
item={
"path": "/fileShares/folder_shared",
"type": "folder",
"id": null,
"clientPath": null,
"info": {
"path": "\\\\server\\share_data\\map_data",
"dataStoreConnectionType": "shared"
}
}