Executing command using SSH.NET produces no output

Question

I am trying to make a program that connects to an SSH server and then logs me in. I have successfully created tracert or ping commands, but SSH connection doesn't work for me at all. I am using SSH.NET. I get no output to my text box. I already followed some advice from StackOverflow (Execute long time command in SSH.NET and display the results continuously in TextBox), but it did not work for me.

Here's the code:

private void button5_Click(object sender, EventArgs e)
{
    string host = "someserverip";
    string username = textBox6.Text;
    string password = textBox8.Text;
    string ipaddress = textBox12.Text;

    using (var radius = new SshClient(host, port, username, password))
    {
        radius.Connect();
        var cmd = radius.CreateCommand("check-host" + ipaddress);
        var result = cmd.BeginExecute();

        using (var reader = new StreamReader(
              cmd.OutputStream, Encoding.UTF8, true, 1024, true))
        {
            while (!result.IsCompleted || !reader.EndOfStream)
            {
                string line = reader.ReadLine();
                if (line != null)
                {
                    textBox10.Invoke(
                        (Action)(() =>
                            textBox10.AppendText(line + Environment.NewLine)));
                }
            }
        }
        cmd.EndExecute(result);
    }
    textBox10.ScrollBars = ScrollBars.Vertical;
}

score 0 · Answer 1 · answered Nov 05 '21 at 16:06

Something probably goes wrong with your command and as you are not reading the error output, you won't know.

Try reading the ExtendedOutputStream to see any error output the command might produce.
To ease debugging you can (temporarily) merge both streams into one using 2>&1 shell syntax.

Though in your code, you miss a space between command name and its arguments. It should rather be

"check-host " + ipaddress

Executing command using SSH.NET produces no output

1 Answers1