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OT: VNC starter applet: Checking up/down behind repeater

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I'd like to check "through" an UltraVNC repeater service, which PCs are up / down: VNCVIEWER.EXE takes many seconds to timeout, before it returns with a connection failed error, that's boring, so I'd like to disable the buttons of "down PCs".

The script itself is running fine:

$title = "V2Go"
$proxy = "" ; VNC Repeater Service, IP & Port
$vnc = @ScriptDir & "\vncvwrtmp.exe"
$Net = "192.168.1."
FileInstall("c:\programme\ultravnc\vncviewer.exe", $vnc, 1)

Dim $aZi[6][3] = [[5], _ ; this is finally used for some ~ 20 PCs
        ["Workstation 1", "101"], _
        ["Workstation 2", "102"], _
        ["Workstation 3", "103"], _
        ["Workstation 4", "104"], _
        ["Workstation n", "10n"]]

;ajust GUI width and height
$max = 0
For $i = 1 To $aZi[0][0]
    If StringLen($aZi[$i][0]) > $max Then $max = StringLen($aZi[$i][0])
$w = $max * 7 + 20
$h = $aZi[0][0] * 25 + 20 + 20

GUICreate($title, $w, $h)
$aZi[1][2] = GUICtrlCreateButton($aZi[1][0], 10, 10, $w - 20, 20)
Opt("GUICoordMode", 2)
For $i = 2 To $aZi[0][0]
    $aZi[$i][2] = GUICtrlCreateButton($aZi[$i][0], -1, 5)
GUICtrlCreateLabel("Esc = Exit", -1, 10, "", "", 1)

While 1
    $msg = GUIGetMsg()
        Case $msg = -3 ; Gui_Event_Close
    For $i = 1 To $aZi[0][0]
        If $msg = $aZi[$i][2] Then
            $CMD = $vnc & " " & $Net & $aZi[$i][1] & " /notoolbar /nostatus /proxy " & $proxy ; WS Access using VNC
            Run($CMD, @ScriptDir)

Who has an idea, how to check qickly what PCs are up and accessible using VNC through a "VNC Repeater Service"[1]?

Any suggestions appreciated,

regards, Rudi.

[1] VNC Repeater:

The VNC Repeater Service is listening at TCP:5901 (default port) on a public accessible IP address.

The VNCVIEWER.EXE client has an option to specify the public IP address of a repeater service. With it's help the viewer can access PCs at the WINVNC port TCP:5900 on a private LAN: The repeater is forwarding the VNC traffic to the local, private LAN.

Earth is flat, pigs can fly, and Nuclear Power is SAFE!

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I Won't help to a project who seems to be a kind of sniffer !

This is not to be a kind of a sniffer, it's more like a "PING to known IPs through the repeater service". The typical thing of "sniffing" is that you grab DATA, that you are not entitled to get aware of. This is not about grabbing data, this is about checking on-/offline status informations of systems, that I ALREADY know all the IP information about.

You will need to know a lot of information[1], so that you can check the up / down status of the workstations. BTW: I'm busy in networking for since 1995 now, and this is intended to ease the service for some of my customers.

So any help for a "Repeater VNC Neighborhood" would be appreciated. By that information I could color the buttons of down WS red and disable them to prevent these boring 30 second timeouts.

If you think, this is not a theme for public discussion you are most welcome do drop me a PM.

But also anybody other's help will be appreciated.

Regards, Rudi.


[1] Repeater's Public IP + port, private IPs + ports of those PC on the local LAN that are intended to accept remote contol service sessions, RC4 encryption key, VNC passwords. After you are VNC connected, you still will need to know the Windows logon name + password, before you finally can access the PC.

Earth is flat, pigs can fly, and Nuclear Power is SAFE!

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Hm, may be I will have to search for an ultravnc forum, as this might be OT?

Another solution would be to config the Cisco firewall to do port forwardings, 5900-> PC1:5900, 5901->PC2:5900, ..., but I dislike this approach: One repeater listening at 5900 looks better to me.

Regards, Rudi.

Edited by rudi

Earth is flat, pigs can fly, and Nuclear Power is SAFE!

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