Polybase external data source using ODBC, login failed error

Question

Using SQL Server 2019 Enterprise Edition (CU14)

I am attempting to use Polybase for reading data from a simple CSV text file.

When executing the create external data source I get the error " Msg 46721, Level 20, State 1 Login failed. The login is from an untrusted domain and cannot be used with Integrated authentication ."

The statement I'm using is:

create external data source datasourcename
with (
  location = 'odbc:\\localhost',
  connection_options='Driver=Microsoft Access Text Driver (*.txt, *.csv); Dbq=d:\data\; ApplicationIntent=ReadOnly;',
  pushdown=off,
  credential = <credential name> -- < On DEV server it works both with/without this
);  

This actually works on my development server, however on the production server it is throwing this error and I can't find a solution. Not really sure what is trying to be logged in to!

On the Dev server (also SQL server 2019/CU14) I can even leave off the credential option and it still works.

Both servers are using the same domain account for the SQL Server service and Polybase services, I have defined the credential identically as:

 create database scoped credential <credential name> with identity = 'Sql Server service domain account', secret = 'domain account password';

I don't think it's relevant but the production server is an Availability-Group secondary replica where I'm trying a simple proof-of-concept to test reading a CSV file and inserting data into TempDB.

On both my Dev server and Production server the file I'm trying to read is located in a folder on a local drive. The drive & folder has full control permissions for the SQL Server Service account.

Both servers have the same odbc driver installed, version 16.00.4999.1000

I have tried adding "trusted_connection=Yes and No" to the connection_options.

Connecting with SSMS I have tried using my own domain account and the SQL Server sa account.

I have installing the "Kerberos Configuration Manager" and connecting to the production server to check the SPNs and it reports "status good".

I have tried adding "DisableLoopbackCheck" registry key on the server.

So far nothing has worked and I'm at a loss as to what else to try.

Answer 1

The external data source definition is wrong: use forward slashes, don't use localhost, the odbc string is missing the curly braces, application intent is not a property of the odbc, and you don't need a credential. See this link for an example: https://36chambers.wordpress.com/2022/02/21/polybase-versus-flat-files/