While doing a search from the site using the Core Results web part, no results were being returned.
On checking ULS logs, we saw errors like:
03/12/2014 22:55:33.01 w3wp.exe (0x446C) 0x666C SharePoint Server Search Query dn0c High CoreResultsDatasourceView: Couldnt find location with internal name LocalSearchIndex 17bc7c9c-9bea-e070-a5b0-675cbbde48b9
03/12/2014 22:55:33.02 w3wp.exe (0x446C) 0x666C SharePoint Server Search Query dn0a High CoreResultsWebpart: Couldnt find location with internal name LocalSearchIndex 17bc7c9c-9bea-e070-a5b0-675cbbde48b9
When we issue a query, we are directed to either the OSSSearchResults.aspx or /Search/Page/results.aspx, the results web part and the web parts in that page will use the LocationConfigurations where this consuming farm failed to have it. It seems that consuming farm is not loading correctly the location configuration from federated location in publishing farm.
Generally the way we fix the missing MSSLocations entries in the DB is to run the following PowerShell
## Set the Search Service Application Variable ##
##Put the name of Search Service Application you created in “ ”##
$ssa = Get-SPEnterpriseSearchServiceApplication “Search Service Application”
## Set the SSA Object to a Disabled State. Moving it from Online to Disabled”
$ssa.Status = “Disabled”
## Update the actual object and the persisted object on the servers ##
## Call the Provision method to invoke a method that should create the OOB location configurations again in the SSA Admin DB ##
This updated the missing MSSLocations entries in the DB and search results came up properly now.
Thanks to Microsoft PFE Sushant Rane who dug this solution up!!!