Connection to MySQL from .NET code over an SSH.NET ForwardedPortLocal does not work

Question

I have to access the database in MySQL that is on the computer with IP (1.1.1.1) with an external network.

I created a tunnel with SSH.NET, but I can't access the IP (1.1.1.1) of the computer where the database is located in MySQL.

Up to the Public IP the tunnel seems to work, but I can't access the Computer IP (1.1.1.1), since I didn't understand how SSH.NET works. Using PuTTY I enter the public IP of the port and in the SSH tunnel section I insert the IP computer (1.1.1.1) with port 3306 and it works very well. The code is this

using (var client = new SshClient("ip public", port, "user", "password")) 
{
    client.Connect();
    if (client.IsConnected)
    {
        var portForwarded = new ForwardedPortLocal("127.0.0.1",22, "1.1.1.1",3306);
        client.AddForwardedPort(portForwarded);
        portForwarded.Start();

        string db = @"Server=127.0.0.1;Port=3306;Database=xxx;Uid=root;Pwd=xxx;";
        {
            var mySQLCon = new MySqlConnection(db);

            mySQLCon.Open();

            if (mySQLCon.State == ConnectionState.Open)
            {
                MainWindow stx = new MainWindow(db);
                stx.ShowDialog();
            }
        }
    }
}

Am I wrong to put the parameters in ForwardedPortLocal?

ForwardedPortLocal("127.0.0.1",22, "1.1.1.1",3306);

I wanted to know if I entered the parameters in ForwardedPortLocal correctly, or where I am wrong in making tunnels with SSH.NET ...

See connectionstrings : https://www.connectionstrings.com/mysql/ — jdweng, Sep 17 '19 at 23:59
If the mysql is running on server 1.1.1.1 then you should have `Server=1.1.1.1` in connection string — Chetan, Sep 18 '19 at 00:27
This tutorial walks you through all the steps: https://mysqlconnector.net/tutorials/connect-ssh/ — Bradley Grainger, Sep 18 '19 at 16:47
BTW I hope you're not actually using `1.1.1.1`, since that's Cloudflare's public DNS resolver: https://www.cloudflare.com/learning/dns/what-is-1.1.1.1/ — Bradley Grainger, Sep 18 '19 at 16:47

Martin Prikryl · Answer 1 · 2020-11-05T05:58:48.680

The boundPort argument of ForwardedPortLocal is the local port which will be forwarded. That's the port that you connect to with MySQL client. So not 22.

While you can hard-code a port like 3306, you better let SSH.NET auto-assign a free local port by omitting that parameter:

var portForwarded = new ForwardedPortLocal("127.0.0.1", "1.1.1.1", 3306);

And then use ForwardedPortLocal.BoundPort in your connection string, instead of hard-coding 3306.

Connection to MySQL from .NET code over an SSH.NET ForwardedPortLocal does not work

1 Answers1