Question

我正在尝试编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是后来声明它无法连接到任何指定的主机？

我配置错了吗？

以下是控制台输出和代码：

enter image description here

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127.0.0.1而不是localhost，或更一般地指定IPAddress.Loopback.ToString（）。此外，您不需要显式转换为uint32。所以你应该尝试类似的东西：

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

如果这不起作用，请尝试指定服务器名称，例如：

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

C＃SSH隧道到MySQL服务器

1 个答案: