Question

I am trying to connect to a remote server (my schools server to access the database) but I am not having any luck i keep getting this

SQL Exception:
State  : 08S01
Message: Communications link failure

Last packet sent to the server was 0 ms ago.
Error  : 0

Here is a code i found in Java, just copied to see if i can connect..

public void test()
 {
    try
    {
       // Load the database driver
       Class.forName( "com.mysql.jdbc.Driver" ) ;

       // Get a connection to the database
       Connection conn = DriverManager.getConnection( "jdbc:mysql://my.db.url.edu;databaseName=marco;user=USERNAME;password=PASSWORD" ) ;

       // Print all warnings
       for( SQLWarning warn = conn.getWarnings(); warn != null; warn = warn.getNextWarning() )
       {
          System.out.println( "SQL Warning:" ) ;
          System.out.println( "State  : " + warn.getSQLState()  ) ;
          System.out.println( "Message: " + warn.getMessage()   ) ;
          System.out.println( "Error  : " + warn.getErrorCode() ) ;
       }

       // Get a statement from the connection
       Statement stmt = conn.createStatement() ;

       // Execute the query
       ResultSet rs = stmt.executeQuery( "SELECT * FROM Test" ) ;

       // Loop through the result set
       while( rs.next() )
          System.out.println( rs.getString(1) ) ;

       // Close the result set, statement and the connection
       rs.close() ;
       stmt.close() ;
       conn.close() ;
   }
   catch( SQLException se )
   {
       System.out.println( "SQL Exception:" ) ;

       // Loop through the SQL Exceptions
       while( se != null )
       {
          System.out.println( "State  : " + se.getSQLState()  ) ;
          System.out.println( "Message: " + se.getMessage()   ) ;
          System.out.println( "Error  : " + se.getErrorCode() ) ;

          se = se.getNextException() ;
       }
   }
   catch( Exception e )
   {
      System.out.println( e ) ;
   }
 }
}

Just to complement the information, I am using Vista. What can be the issue?

Regards

Answer 1

There are many possible reasons why you get ‘link failure’ while connecting to your databse.

1. Firewalls and/or routers blocking your connection to the db
2. The database itself doesn’t allow remote connection

If you are sure that case 2 doesn’t apply you would have to check things on your side, switch off your antivirus/firewall software on development machine, if that doesn’t work contact the db administrator.