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Port Forwarding

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mendotaView
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Port Forwarding

Post by mendotaView »

I would like to use uvnc to do customer support. Most of my customers are in institutions where they do not have passwords for the router. Can the uvnc server be configured so the it uses NAT to create an open (external) port for logging on?
Thanks,
Peter
mhertz
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Re: Port Forwarding

Post by mhertz »

Ultravnc supports reverse connections, for situations where the remote-user cannot open required ports themselves. The remote user can do it manually if given your IP/URL, or you can e.g. add this command to there ultravnc.ini "-autoreconnect -connect <IP/URL>" and then you can connect to them, when they start the ultravnc service(or if autostarted), provided you have port 5500(or whatever) opened on your end. You can also make a desktop shortcut for the remote-user to doubleclick, which make this reverse connection to you through ultravnc application mode(instead of service mode). Lastly, theres also ultravnc SC which makes you make a premade EXE to send to the remote-user and which reverse connects back to you through hardcoded IP/URL.
mendotaView
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Re: Port Forwarding

Post by mendotaView »

Thanks mertz,
However, it looks like these solution require my having ports forwarded on my (client) end. Since the client computer is apt to be a laptop using hotel internet of a Verizon jetpack, I'm not sure that is prectical either.
Would it help to set up an always-on computer at my office, with ports forwarded, for both the client and the server to connect to to get started?
mhertz
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Re: Port Forwarding

Post by mhertz »

I thought only the remote-end(them) had forewarding issues, sorry. If the local-end(you)also is firewalled/nat'ted, then luckily ultravnc also supports this scenario, through it's repeater option: http://www.uvnc.com/products/uvnc-repeater.html
mendotaView
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Re: Port Forwarding

Post by mendotaView »

Actually, port forwarding on my jetpack looks easy now. I suppose I would create a 'custom' forward. Does it matter what I call it?
Port 5900 for the server, and 5500 for the SC option?
Does a port need to be assigned for html (it looks like it is in the server admin properties)?
mhertz
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Re: Port Forwarding

Post by mhertz »

No, it doesn't matter the naming, solely port number and type(TCP).

Yes, unless wanting to change them from default, then 5900 for server, and 5500 for reverse-connections with ultravnc regular or SC version, as you stated.

No, you don't need to foreward port 5800 if not using the servers internal java-viewer option, e.g. I don't. It's for so you have the option of connecting to a server without needing a viewer, only need java installed. Good luck! :)
mendotaView
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Re: Port Forwarding

Post by mendotaView »

I got into my verizon jetpack and forwarded port 5900, but the port checker still says that port is closed. When forwarding it had options for global port and local port so I put 5900 in for both. I cannot connect to the WAN ip address from a different computer.
I tried it with the server open and closed. Does that matter for whether the port is 'open'?
running 'netstat -a' on the command line also shows nothing for 5900.
The firewall has a hole for that port, and i tried it with firewall off too.
Do you think Verizon blocks the ports further up the chain?
mhertz
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Re: Port Forwarding

Post by mhertz »

Hmm, sorry, I don't know if the reason is that the port is blocked by verizon? Could well be... Yes, it matters if the server is running or not - a port only lists OPEN when the port is forewarded properly AND something is actively listening for it, so with the tests you need to have the server running. Yes, global/local port should be the same. Make sure you have the proper port defined in ultravnc and try with other port numbers just in case. Finally, go through your router and check if everything is correct e.g. on my router I had to both make the rule and additionally select another option for enabling these rules - check that there isn't a firewall to also be disabled/changed on the router. Also, make sure you don't have other security-suits installed with built-in firewall. As a last resort, you can usually also enable your computer(local IP) to be a DMZ server in the router. This means that all ports are open on that local IP(routed through WAN), and then check if it works with that, just as a troubleshoot. Reboot just in case too.

Sorry I cannot be of more help than this. Good luck.
mendotaView
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Re: Port Forwarding

Post by mendotaView »

I downloaded NVC.exe and NSC.exe, as NAT2NAT looks like it connects without port forwarding. But I'm a little mystified. Is the 'helper' something I need to put on my computer, or is it in running somewhere else?
The .exe utilities ask for ID and password, from where? There's a password on my uvnc server, but I don't see an ID.
Is there an ID and password on the viewer? It is not my uvnc forum ID and password is it?
Thanks,
mhertz
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Re: Port Forwarding

Post by mhertz »

I'm sorry, I cannot help really with repeater and whatnot other options, sorry... I know they exist, but have zero knowledge about it otherwise as have never had a need to use it currently, as if the remote user cannot forward ports, then atleast I can do that and make a reverse connection to them through normal ultravnc or SC without helpers. I think the repeater needs to run on a seperate PC with forwarded ports and then you use that as a proxy between you and them. You connect with eachother through ID/password, and I think it's not the ultravnc password, but a special repeater password, like how teamviewer and the rest works(i.e. act as repeater).

Here's a really old guide from a quick google, but there's surely newer/better guides available if googling more:

UltraVNC Repeater Guide:
http://www.bevingtontechnologies.com/ww ... bystep.pdf

Sorry, and good luck.
mendotaView
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Re: Port Forwarding

Post by mendotaView »

That doc is a great introduction.
Thanks
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