C＃到MySQL服务器的SSH隧道

Question

我想写一个简单的程序来连接到只能通过SSH连接的MySQL远程服务器。

它报告SSH连接并且端口转发，但表明它无法连接到任何指定的主机？

我配置了这个错误吗？

下面是控制台输出和代码：

using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Diagnostics; 
using System.IO; 
using System.Data; 
using System.Web; 
using System.Windows.Forms; 
//Add MySql Library 
using MySql.Data.Entity; 
using MySql.Data.MySqlClient; 
using MySql.Data.Types; 

// SSH 
using Renci.SshNet; 
using Renci.SshNet.Common; 

namespace MySQL_Console 
{ 
    class MainClass 
    { 

     public static void Main (string[] args) 
     { 
      PasswordConnectionInfo connectionInfo = new PasswordConnectionInfo ("mytestdb.co.uk", "root", "password123"); 
      connectionInfo.Timeout = TimeSpan.FromSeconds (30); 

      using (var client = new SshClient(connectionInfo)) { 
       try 
       { 
        Console.WriteLine ("Trying SSH connection..."); 
        client.Connect(); 
        if (client.IsConnected) 
        { 
         Console.WriteLine ("SSH connection is active: {0}", client.ConnectionInfo.ToString()); 
        } 
        else 
        { 
         Console.WriteLine ("SSH connection has failed: {0}", client.ConnectionInfo.ToString()); 
        } 

        Console.WriteLine ("\r\nTrying port forwarding..."); 
        var portFwld = new ForwardedPortLocal(Convert.ToUInt32(4479), "localhost", Convert.ToUInt32(3306)); 
        client.AddForwardedPort(portFwld); 
        portFwld.Start(); 
        if (portFwld.IsStarted) 
        { 
         Console.WriteLine ("Port forwarded: {0}", portFwld.ToString()); 
        } 
        else 
        { 
         Console.WriteLine ("Port forwarding has failed."); 
        } 

       } 
       catch (SshException e) 
       { 
        Console.WriteLine ("SSH client connection error: {0}", e.Message); 
       } 
       catch (System.Net.Sockets.SocketException e) 
       { 
        Console.WriteLine ("Socket connection error: {0}", e.Message); 
       } 

      } 

      Console.WriteLine ("\r\nTrying database connection..."); 
      DBConnect dbConnect = new DBConnect ("localhost", "test_database", "root", "passwrod123", "4479"); 

      var ct = dbConnect.Count ("packages"); 
      Console.WriteLine (ct.ToString()); 
     } 
    } 

    // MySQL DB class 
    class DBConnect 
    { 
     private MySqlConnection connection; 

     private string server; 
     public string Server 
     { 
      get 
      { 
       return this.server; 
      } 
      set 
      { 
       this.server = value; 
      } 
     } 

     private string database; 
     public string Database 
     { 
      get 
      { 
       return this.database; 
      } 
      set 
      { 
       this.database = value; 
      } 
     } 

     private string uid; 
     public string Uid 
     { 
      get 
      { 
       return this.server; 
      } 
      set 
      { 
       this.server = value; 
      } 
     } 

     private string password; 
     public string Password 
     { 
      get 
      { 
       return this.password; 
      } 
      set 
      { 
       this.password = value; 
      } 
     } 

     private string port; 
     public string Port 
     { 
      get 
      { 
       return this.port; 
      } 
      set 
      { 
       this.port = value; 
      } 
     } 

     //Constructor 
     public DBConnect(string server, string database, string uid, string password, string port = "3306") 
     { 
      this.server = server; 

      this.database = database; 
      this.uid = uid; 
      this.password = password; 
      this.port = port; 

      Initialize(); 
     } 

     //Initialize values 
     private void Initialize() 
     { 
      string connectionString; 
      connectionString = "SERVER=" + server + ";" + "DATABASE=" + database + ";" + "UID=" + uid + ";" + "PASSWORD=" + password + ";"; 
      connection = new MySqlConnection(connectionString); 
     } 


     //open connection to database 
     private bool OpenConnection() 
     { 
      try 
      { 
       connection.Open(); 
       Console.WriteLine("MySQL connected."); 
       return true; 
      } 
      catch (MySqlException ex) 
      { 
       //When handling errors, you can your application's response based on the error number. 
       //The two most common error numbers when connecting are as follows: 
       //0: Cannot connect to server. 
       //1045: Invalid user name and/or password. 
       switch (ex.Number) 
       { 
        case 0: 
        Console.WriteLine("Cannot connect to server. Contact administrator"); 
        break; 

        case 1045: 
        Console.WriteLine("Invalid username/password, please try again"); 
        break; 

        default: 
        Console.WriteLine("Unhandled exception: {0}.", ex.Message); 
        break; 

       } 
       return false; 
      } 
     } 

     //Close connection 
     private bool CloseConnection() 
     { 
      try 
      { 
       connection.Close(); 
       return true; 
      } 
      catch (MySqlException ex) 
      { 
       Console.WriteLine(ex.Message); 
       return false; 
      } 
     } 

     //Insert statement 
     public void Insert() 
     { 
      string query = "INSERT INTO tableinfo (name, age) VALUES('John Smith', '33')"; 

      //open connection 
      if (this.OpenConnection() == true) 
      { 
       //create command and assign the query and connection from the constructor 
       MySqlCommand cmd = new MySqlCommand(query, connection); 

       //Execute command 
       cmd.ExecuteNonQuery(); 

       //close connection 
       this.CloseConnection(); 
      } 
     } 

     //Update statement 
     public void Update(string tableName, List<KeyValuePair<string, string>> setArgs, List<KeyValuePair<string, string>> whereArgs) 
     { 
      string query = "UPDATE tableinfo SET name='Joe', age='22' WHERE name='John Smith'"; 

      //Open connection 
      if (this.OpenConnection() == true) 
      { 
       //create mysql command 
       MySqlCommand cmd = new MySqlCommand(); 
       //Assign the query using CommandText 
       cmd.CommandText = query; 
       //Assign the connection using Connection 
       cmd.Connection = connection; 

       //Execute query 
       cmd.ExecuteNonQuery(); 

       //close connection 
       this.CloseConnection(); 
      } 
     } 

     //Delete statement 
     public void Delete(string tableName, List<KeyValuePair<string, string>> whereArgs) 
     { 
      string query = "DELETE FROM tableinfo WHERE name='John Smith'"; 

      if (this.OpenConnection() == true) 
      { 
       MySqlCommand cmd = new MySqlCommand(query, connection); 
       cmd.ExecuteNonQuery(); 
       this.CloseConnection(); 
      } 
     } 

     //Select statement 
     public List<string> Select(string queryString) 
     { 
      string query = queryString; 

      //Create a list to store the result 
      List<string> list = new List<string>(); 

      //Open connection 
      if (this.OpenConnection() == true) 
      { 
       //Create Command 
       MySqlCommand cmd = new MySqlCommand(query, connection); 
       //Create a data reader and Execute the command 
       MySqlDataReader dataReader = cmd.ExecuteReader(); 

       //Read the data and store them in the list 
       int fieldCOunt = dataReader.FieldCount; 
       while (dataReader.Read()) 
       { 
        for (int i = 0; i < fieldCOunt; i++) { 
         list.Add(dataReader.GetValue(i).ToString()); 
        } 
       } 

       //close Data Reader 
       dataReader.Close(); 

       //close Connection 
       this.CloseConnection(); 

       //return list to be displayed 
       return list; 
      } 

      return list; 

     } 

     //Count statement 
     public int Count(string tableName) 
     { 
      string query = "SELECT Count(*) FROM " + tableName; 
      int Count = -1; 

      //Open Connection 
      if (this.OpenConnection() == true) 
      { 
       //Create Mysql Command 
       MySqlCommand cmd = new MySqlCommand(query, connection); 

       //ExecuteScalar will return one value 
       Count = int.Parse(cmd.ExecuteScalar()+""); 

       //close Connection 
       this.CloseConnection(); 

       return Count; 
      } 

      return Count; 

     } 

     //Backup 
     public void Backup() 
     { 
      try 
      { 
       DateTime Time = DateTime.Now; 
       int year = Time.Year; 
       int month = Time.Month; 
       int day = Time.Day; 
       int hour = Time.Hour; 
       int minute = Time.Minute; 
       int second = Time.Second; 
       int millisecond = Time.Millisecond; 

       //Save file to C:\ with the current date as a filename 
       string path; 
       path = "C:\\" + year + "-" + month + "-" + day + "-" + hour + "-" + minute + "-" + second + "-" + millisecond + ".sql"; 
       StreamWriter file = new StreamWriter(path); 


       ProcessStartInfo psi = new ProcessStartInfo(); 
       psi.FileName = "mysqldump"; 
       psi.RedirectStandardInput = false; 
       psi.RedirectStandardOutput = true; 
       psi.Arguments = string.Format(@"-u{0} -p{1} -h{2} {3}", uid, password, server, database); 
       psi.UseShellExecute = false; 

       Process process = Process.Start(psi); 

       string output; 
       output = process.StandardOutput.ReadToEnd(); 
       file.WriteLine(output); 
       process.WaitForExit(); 
       file.Close(); 
       process.Close(); 
      } 
      catch (IOException e) 
      { 
       Console.WriteLine("Error {0}, unable to backup!", e.Message); 
      } 
     } 

     //Restore 
     public void Restore() 
     { 
      try 
      { 
       //Read file from C:\ 
       string path; 
       path = "C:\\MySqlBackup.sql"; 
       StreamReader file = new StreamReader(path); 
       string input = file.ReadToEnd(); 
       file.Close(); 


       ProcessStartInfo psi = new ProcessStartInfo(); 
       psi.FileName = "mysql"; 
       psi.RedirectStandardInput = true; 
       psi.RedirectStandardOutput = false; 
       psi.Arguments = string.Format(@"-u{0} -p{1} -h{2} {3}", uid, password, server, database); 
       psi.UseShellExecute = false; 


       Process process = Process.Start(psi); 
       process.StandardInput.WriteLine(input); 
       process.StandardInput.Close(); 
       process.WaitForExit(); 
       process.Close(); 
      } 
      catch (IOException e) 
      { 
       Console.WriteLine("Error {0}, unable to Restore!", e.Message); 
      } 
     } 
    } 
} 

Answer 1

尝试指定的而不是本地主机127.0.0.1，或者更一般IPAddress.Loopback.ToString（）。另外，你不需要明确地投射到uint32。所以，你应该尝试类似：

var portFwld = new ForwardedPortLocal(4479, IPAddress.Loopback.ToString(), 3306); 

如果不行，请尝试同时指定服务器名称，类似：

var portFwld = new ForwardedPortLocal(IPAddress.Loopback.ToString(), 4479, "servername_goes_here", 3306);