VBScript

Stop an SSH Tunnel Listener (StopAccepting)

Demonstrates the Chilkat SshTunnel.StopAccepting method, which stops the local listener so no new client connections are accepted. The only argument (waitForThread) selects whether to wait for the listener thread to exit. Existing forwarded clients remain connected.

Background: The distinction from CloseTunnel is the point: StopAccepting closes only the front door, leaving already-connected clients to finish their transfers undisturbed. That makes it the graceful way to drain a tunnel — stop taking new work, let existing work complete, then close — rather than cutting everyone off at once.

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VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

'  Demonstrates the SshTunnel.StopAccepting method, which stops the local listener so that no new
'  client connections are accepted.  The only argument (waitForThread) selects whether to wait for
'  the listener thread to exit.  Existing forwarded clients remain connected.

set tunnel = CreateObject("Chilkat.SshTunnel")

tunnel.DestHostname = "db.internal.example.com"
tunnel.DestPort = 5432

sshPort = 22
success = tunnel.Connect("ssh.example.com",sshPort)
If (success = 0) Then
    outFile.WriteLine(tunnel.LastErrorText)
    WScript.Quit
End If

'  Normally you would not hard-code the password in source.  You should instead obtain it
'  from an interactive prompt, environment variable, or a secrets vault.
password = "mySshPassword"

success = tunnel.AuthenticatePw("mySshLogin",password)
If (success = 0) Then
    outFile.WriteLine(tunnel.LastErrorText)
    WScript.Quit
End If

listenPort = 1080
success = tunnel.BeginAccepting(listenPort)
If (success = 0) Then
    outFile.WriteLine(tunnel.LastErrorText)
    WScript.Quit
End If

'  ... the tunnel runs for a while ...

'  Stop accepting NEW connections, but leave already-connected clients running.
waitForThread = 1
success = tunnel.StopAccepting(waitForThread)
If (success = 0) Then
    outFile.WriteLine(tunnel.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine("The listener has stopped; existing clients continue.")

waitForThreadExit = 1
success = tunnel.CloseTunnel(waitForThreadExit)
If (success = 0) Then
    outFile.WriteLine(tunnel.LastErrorText)
    WScript.Quit
End If


outFile.Close