[SOLVED] Azure sql connection hangs using JTDS

Azure sql connection hangs using JTDS

I am trying to connect to an Azure SQL server using the JTDS JDBC driver. I have gotten the connection to work previously, but overnight it now hangs on

DriverManager.getConnection(url);

It gives me no exception, and continues running past the 30 second timeout that is default in the connection string. Full code is below

        try {
            StrictMode.ThreadPolicy pol = new StrictMode.ThreadPolicy.Builder().permitAll().build();
            StrictMode.setThreadPolicy(pol);

            Class.forName("net.sourceforge.jtds.jdbc.Driver");
            String url = "jdbc:jtds:sqlserver://{server}.database.windows.net:1433;database=PROD;user={username}@{server};password={password};encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;";
            Connection c = DriverManager.getConnection(url);

            c.close();
        }
        catch(Exception e)
        {
            new AlertDialog.Builder().setTitle("e").setMessage(e.getMessage()).setNegativeButton("e", null).show();
        }

I am able to connect to and query the database using SSMS, so as far as I can tell the database is working correctly. Though I am a very beginner on using SQL servers so I may be wrong. I found that the SQL server version is 12.0.2000.8. JTDS documentation suggests changing the TDS version in some cases, but from what I tried that didnt solve my issues. I am using JTDS version 1.3.1.

Again, this method was working fine yesterday and now I am having issues. Nothing in the project was changed. Yesterday I wasn't closing the connection after creating it, so I have a hunch that there is some issue with that on the SQL Server.

Now, a couple hours later, the connection went through after a few seconds, and when I tried to rerun the app it had the same issue.

Found my solution:

Seems that the android emulator had an issue with DNS. Following Android Studio - Android Emulator Wifi Connected with No Internet this thread I was able to manually set my DNS to 8.8.8.8 and 8.8.4.4 which resolved the issue.

Solution

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