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NAT2NAT question

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marek_g
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NAT2NAT question

Post by marek_g »

Hello everyone,

I'm new to VNC and I've searched through the FAQ and many guides but I couldn't find the required information, so here's my question.
I have a server with public IP address and I've successfully setup a VNC Repeater on it and I'm able to connect two computers with VNC Viewer and VNC SingleClick (ChunkVNC) through it (both computers are on different LAN's behind NAT's).
But SingleClick has two major problems:
1. It cannot run as a service (so no logon or UAC support)
2. Antivirus software detect it as malware.
So I've installed full UltraVNC (Server with Viewer) on the computer that I want connect to, but it seems that it requires port forwarding to connect to it from the Internet (WAN).
I cannot forward any ports so is it possible to connect a VNC Server to the Repeater so I can connect to the server?
Or maybe there are some other ways to do it?
Thanks in advance.
YY
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Posts: 996
Joined: 2006-11-13 15:11

Re: NAT2NAT question

Post by YY »

Yes, you can configure the UVNC server to connect to a repeater automatically when it is running as a service.

You just need to add the instruction to the service_commandline, which is a setting inside the file "ultravnc.ini". You can find the file at the installed folder of Ultravnc, and modify it with a text editor

Your setting should be something like that:

Code: Select all

service_commandline=-autoreconnect ID -connect Repeater_IP:5500
marek_g
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Re: NAT2NAT question

Post by marek_g »

Thank you YY, it worked - the server has registered on the repeater with the ID I've specified (I see it in the repeater's Log window).
I only had to add the [admin] option it the .ini file.
But still I cannot connect to the server through the repeater - I've tried changing the "Auto" option to "Display number" and to different ports - I just can't connect whether it's Display No. or Port.
While I was testing different options sometimes there was "connection accept" entry in the repeater's Log window and sometimes it was "proxy read erro".
Could you please guide me through the rest of configuration?
I mean, when the repeater listens on two different ports (Viewer and Server) then which port I should specify in the repeater IP address section in Viewer?
And I understand that in the Viewer I should specify the server's ID with it's port or display number - am I correct?
I really don't know what's wrong...
YY
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Joined: 2006-11-13 15:11

Re: NAT2NAT question

Post by YY »

OK. I will try to provide a step by step procedure here. Of course, I just assume the general condition, as I can't take care if any firewall or antivirus that may block the VNC traffic.

1. First of all, just let the UVNC server working under "Auto". The Display or Ports settings are not taking part when connection to the repeater. And the command mentioned before had been entered into the "ultravnc.ini"

2. For the repeater, use the setting as the picture below:
 Sorry, the picture is not completely correct, the "Listen port viewer" should be 5901 (not 5501)
Image


3. At the viewer, enter the ID and Repeater IP & Port as below:
Image


4. Also, click the Viewer's Option...., at the box of "reconnection attempts", enter a positive digit (say: 5) to replace the original 0.
Image
You may see this thread for a brief explanation by the developer:
http://forum.ultravnc.info/viewtopic.ph ... 19&start=4


Now you may try the connection. Hope you will be success.
marek_g
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Re: NAT2NAT question

Post by marek_g »

Thank you soo much, YY!
It's like you saved my life 8)
Everything worked like it should; maybe it's just me but I think that the options in the Viewer should be described more intuitive because I think the only problem was me typing "ID:PORT" instead of "ID:1234".
Anyway UVNC is a great software, I just love the opensource.
I just started using UVNC because you can't connect to a lot of different computers and servers with TeamViewer for free anymore.
I think a lot of people will start to use UVNC just like me and I hope this thread will be helpfull to a lot of them 8)
marek_g
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Re: NAT2NAT question

Post by marek_g »

OK, so I'm successfully connecting different computers with each other through Repeater but there is one problem - the Server's doesn't ask for password.
I get "Password accepted" on the Viewer and I just connect to another computer without specifying any password.
I've already tried to set the password in Admin Options on the Server - it just doesn't matter.
So what should I do to secure the Servers with password?
And also how do I secure the Repeater from unauthorized connections?
Thanks in advance.
YY
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Posts: 996
Joined: 2006-11-13 15:11

Re: NAT2NAT question

Post by YY »

When UltraVNC connection is established with Reverse Connection, or Mode II Repeater Connection (i.e. the setup you are running), the password authentication will be omitted.

However, you may grant this feature again if using the SecureVNC plugin, as it has its own password authentication setting and always be used in every type of connection mode. Also there is an advantage that the VNC communication is encrypted.

SecureVNC plugin, see:
http://forum.ultravnc.info/viewtopic.php?f=10&t=15840
marek_g
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Re: NAT2NAT question

Post by marek_g »

Thank you YY, everything worked!
BTW: The Repeater can be secured via it's Settings window and by allowing connections only from specified ID's.
marek_g
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Re: NAT2NAT question

Post by marek_g »

OK, there is a problem with my first UVNC server.
Yesterday everything was working good but suddenly the server stopped registering on the repeater and I couldn't re-connect to it.
I had to restart the "uvnc_service" service on the server and it helped.
Is there any way to prevent this from happenning again?
I know that for example I could schedule an automatic service restart but it's not the best idea...
marek_g
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Re: NAT2NAT question

Post by marek_g »

Regarding my previous post it may be my fault - I've used an old Repeater version.
I've installed a new one and I'll test it.
marek_g
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Re: NAT2NAT question

Post by marek_g »

Well, I've installed the latest Repeater version as a service, but still the server drops the connection with it.
Any help is appreciated.
marek_g
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Posts: 15
Joined: 2014-08-31 14:54

Re: NAT2NAT question

Post by marek_g »

OK, just installed the latest (1.2.0.3) Server and Viewer and everything works just great :-D
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