Authenticating to a SQL Server instance as a Windows User via JDBC

Question

I\'m having to support multiple database types for my tenant-enabled web application. Among others, I have successfully supported Microsoft\'s SQL Server, by using the net.s

Answer 1

I can see two possibilities, 1. You are using a local system account which the server won't understand In this case, switch to a domain account.

2. Windows authentication has different credential requirements and you might not be meeting those. In this case try changing the password to match the requirements.

It is very well possible that both are happening.

Answer 2

The main problem is the windows authentication with a full java solution (no DLL). So you could use one of the libs below:

• NTLM authentication: http://ioplex.com/jespa.html
• spring based Kerberos authentication: http://projects.spring.io/spring-security-kerberos/
• another integrated windows auth lib is SPNEGO (don't know much about this one)

So once your app is authenticated with one of the lib above, your JDBC should run fine using "integratedSecurity=true;" and if needed "authenticationScheme=JavaKerberos".

Answer 3

I ran into the error

The login is from an untrusted domain and cannot be used with Windows authentication

when a 2012 SQL Server DB instance was recently upgraded to 2016. In order to use AD based authentication with the JTDS driver and SQL Server 2016, it seems necessary to specify both the useNTLMv2=true and the domain=example.com suffix in order to establish a connection. The name of the domain is absolutely necessary and I confirmed that through testing. This is with JTDS driver version 1.3.1.

Example of a working connection string using AD based authentication to SQL Server 2016 DB with JTDS 1.3.1:

jdbc:jtds:sqlserver://sqlserver2016db.example.com/MY_DB_NAME;domain=example.com;prepareSQL=2;useNTLMv2=true

Answer 4

see this other SO post that describes how to connect to a SQL Server with Windows Authentication from a Linux machine through JDBC

Answer 5

What you describe certainly appears to be feasible. I have SQL Server 2008 R2 Express running on a stand-alone server and I was able to connect using a Windows username/password on that server via jTDS 1.3.1 from a separate Windows machine and from an Xubuntu 14.04 box.

On the machine running SQL Server I created a Windows user named 'kilian'. In SQL Server itself I created a SQL Login for NT AUTHORITY\Authenticated Users. Then in the database (named 'myDb') I created a User named 'AuthenticatedUsers' for that SQL Login. Just to keep things simple I gave that user db_owner rights on the database.

There is no SQL Login for 'kilian' and no database User with that name.

Then, from the other two machines (the Windows workstation and the Xubuntu box) I just ran this:

package com.example.jtdstest;

import java.sql.*;

public class JtdsTestMain {

    public static void main(String[] args) {
        try (Connection con = DriverManager.getConnection(
                "jdbc:jtds:sqlserver://192.168.1.137:52865/myDb" +
                    ";domain=whatever",
                "kilian",
                "4theBounty")) {
            try (Statement s = con.createStatement()) {
                String sql = "SELECT LastName FROM Clients WHERE ID=1";
                try (ResultSet rs = s.executeQuery(sql)) {
                    rs.next();
                    System.out.println(rs.getString("LastName"));
                }
            }
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }

    }

}

Additional notes:

• I did not have to include useNTLMv2=true. I was able to connect with or without that parameter.

• I did have to include domain= to tell the SQL Server not to use SQL authentication, but the actual value I supplied made no difference. (I literally used 'whatever', which was not the name of the server or the name of the workgroup to which it belongs.)

Answer 6

Firstly you should write the jdbc connection like this:

String url ="jdbc:sqlserver://PC01\inst01;databaseName=DB01;integratedSecurity=true";

then

you need to enable the SQL Server TCP/IP Protocol in Sql Server Configuration Manager app. You can see the protocol in SQL Server Network Configuration.