New Post: on cisco router no response after send Enable

    Class switchSshSession
        Inherits switchSession
        Private SSHPasswordConnection As Renci.SshNet.PasswordAuthenticationMethod
        Private SSHKeyboardInteractive As Renci.SshNet.KeyboardInteractiveAuthenticationMethod
        Private SSHConnectionInfo As Renci.SshNet.ConnectionInfo
        Private ClientSsh As Renci.SshNet.SshClient = Nothing
        Private SSHShell As Renci.SshNet.Shell = Nothing
        Private SSHStream As Renci.SshNet.ShellStream
        Private SSHreader As StreamReader
        Private SSHwriter As StreamWriter

        Public Sub New(scriptText As String, ResponseWait As Integer, ResponseRetries As Integer)
            ' The switchSshSession New call's base class New to fill ScriptSend and ScriptWait
            ' and performs the SSH session setup

            MyBase.New(scriptText, ResponseWait, ResponseRetries)
            ClientPort = 22

            Try
                ' if PasswordAuthentication is requested (demanded) by the switch, we can handle that
                SSHPasswordConnection = New Renci.SshNet.PasswordAuthenticationMethod(ClientUsername, ClientPassword)
                SSHKeyboardInteractive = New Renci.SshNet.KeyboardInteractiveAuthenticationMethod(ClientUsername)
                SSHConnectionInfo = New Renci.SshNet.ConnectionInfo(ClientIP, ClientPort, ClientUsername, SSHPasswordConnection, SSHKeyboardInteractive)

                AddHandler SSHKeyboardInteractive.AuthenticationPrompt, AddressOf SSHhandleKeyboardAuthentication

                ClientSsh = New Renci.SshNet.SshClient(SSHConnectionInfo)
                ClientSsh.ConnectionInfo.Timeout = TimeSpan.FromSeconds(10)
                ClientSsh.ConnectionInfo.RetryAttempts = 3
                ClientSsh.Connect()

                If ClientSsh.IsConnected = False Then
                    Throw New Exception("connection failed")
                    Exit Sub
                End If

                SSHStream = ClientSsh.CreateShellStream("xterm", 80, 24, 800, 600, 1024)
                SSHreader = New StreamReader(SSHStream)
                SSHwriter = New StreamWriter(SSHStream)
                SSHwriter.AutoFlush = True
                Thread.Sleep(ClientResponseWait)
                SSHreader.ReadToEnd()

            Catch ex As Exception
                sessionStatus = ex.Message & " connecting " & ClientIP & " port " & ClientPort & " (SSH)"
                ClientValid = False
            End Try

        End Sub
        Public Overloads Function ExecuteScript() As Boolean
            ' perform SSH i/o
            '
            ' In the While loop the commands in ScriptSend are send and responses in ScriptWait are 
            ' (substring) matched to the received response.
            ' SSHReadResult does the actual reading.
            ' The ClientResponse is build up as we go along, replacing passwords with *******

            ExecuteScript = False

            Dim sendString As String = ""
            Dim waitString As String = ""
            Dim receivedString As String = ""
            Dim PasswordSkip As Boolean = False
            sessionIOindex = 3 ' ssh offset 3: 0 = ip, 1 = username, 2 = password
            Try

                While sessionIOindex < ScriptSend.Length
                    sendString = ScriptSend(sessionIOindex)
                    waitString = ScriptWait(sessionIOindex)

                    SSHStream.Write(sendString & vbCr)          ' send command
                    receivedString = SSHReadResult(waitString)  ' read result

                    If receivedString.IndexOf(waitString, 0, receivedString.Length, StringComparison.CurrentCultureIgnoreCase) < 0 Then
                        Throw New Exception("received: '" & receivedString & "' waiting for: '" & waitString & "'")
                    End If

                    If PasswordSkip Then
                        ClientResponse += "*******"
                    Else
                        ClientResponse += receivedString
                    End If
                    ClientResponse += Environment.NewLine

                    PasswordSkip = False
                    If receivedString.IndexOf("password", 0, receivedString.Length, StringComparison.CurrentCultureIgnoreCase) >= 0 Then
                        PasswordSkip = True
                    End If
                    sessionIOindex += 1
                End While
                ExecuteScript = True

            Catch ex As Exception
                sessionStatus = ex.Message & Environment.NewLine & "send [ " & sendString & _
                    " ] to " & ClientIP & " (SSH), expecting response to contain [ " & waitString & " ] (script-index " & sessionIOindex * 2 & ")"
                ExecuteScript = False
            End Try
        End Function
        Private Sub SSHhandleKeyboardAuthentication(sender As Object, e As Renci.SshNet.Common.AuthenticationPromptEventArgs)
            For Each prompt As Renci.SshNet.Common.AuthenticationPrompt In e.Prompts
                If prompt.Request.Equals("Password: ", StringComparison.InvariantCultureIgnoreCase) Then
                    prompt.Response = ClientPassword
                End If
            Next
        End Sub
        Private Function SSHReadResult(Expected As String) As String
            ' Read the result from SSHreader until Expected is read.
            ' Commands issued to the switch may require some processing. Not all data may be available at once, so give em some slack.
            ' We asume the command send to allways be received by the switch
            Dim strRead As String = ""
            Dim retries As Integer = 0
            Try
                Thread.Sleep(ClientResponseWait)        ' give IOS a first change to form the response
                strRead = SSHreader.ReadToEnd

                While retries < ClientResponseRetries
                    If strRead.IndexOf(Expected, 0, strRead.Length, StringComparison.CurrentCultureIgnoreCase) < 0 Then
                        retries += 1
                        Thread.Sleep(ClientResponseWait)
                        If SSHStream.DataAvailable Then
                            strRead += SSHreader.ReadToEnd   ' append to data already received
                        End If
                    Else
                        Exit While
                    End If
                End While

                Return (strRead)

            Catch ex As Exception
                Return (Nothing)
            End Try
        End Function
        Public Overloads Sub Dispose()
            MyBase.Dispose()
            On Error Resume Next
            SSHreader.Close()
            SSHreader.Dispose()
            SSHwriter.Close()
            SSHwriter.Dispose()
            SSHShell.Dispose()
            Err.Clear()
        End Sub
    End Class