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Local LAN works but not WAN

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FMinMI
Posts: 5
Joined: 2010-12-14 23:24

Local LAN works but not WAN

Post by FMinMI »

Hello all,

I just found UltraVNC after getting totally frustrated with pcAnywhere 12.5. I just purchased a new computer so that both computers are running WIN 7 and pcAnywhere is not working worth a darn. So I read, downloaded and installed UltraVNC on my MAIN computer (as UltraVNC SERVER ONLY, NO optional non-GPL addons, NO mirror driver, selected all 4 additional tasks). During installation it did complain about not finding a folder but I continued. I then did the same install on the laptop but as viewer only.

My MAIN computer has a static IP address of 192.168.0.2 and I use dyndns to keep the static name "ABCXXX.dyndns.ws" (phony name of course) updated outside of my LAN to the correct IP address. In my router (Dlink DIR-655), I did port forwarding to 192.168.0.2 for TCP ports 5500, 5800, 5900. Also, under application rules I have the same port trigger/firewall set to TCP (5500,5800,5900). I did save these settings and rebooted the router.

After installing UltraVNC on the laptop and starting it up, I can tell it to go to 192.168.0.2 and the UltraVNC works fine. It is when I try to connect to ABCXXX.dyndns.ws that it fails. I even tried the risky setting of DMZ to 192.168.0.2 but it too did not work.

I re-read all the port info to make sure I did not miss a port. I have not installed any antivirus software on the MAIN computer yet (just got it and wanted to get everything else set first). On the laptop I have NIS 2011 and turned off everything for 15 minutes while testing. I know it has to be either a firewall or port issue as I can connect inside my LAN. Any suggestions for where I went wrong / what I need to change would be appreciated.

Thank you.

Frank
Michigan
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supercoe
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Re: Local LAN works but not WAN

Post by supercoe »

Many routers do not support NAT loopback, without this feature you will not be able to connect to "ABCXXX.dyndns.ws" from within your LAN.

Try using http://www.yougetsignal.com to check if you opened the ports for UltraVNC correctly or try from a computer outside of your LAN.
http://www.chunkvnc.com - ChunkVNC - Free PC Remote control with the Open Source UltraVNC wrapper InstantSupport!
FMinMI
Posts: 5
Joined: 2010-12-14 23:24

Re: Local LAN works but not WAN

Post by FMinMI »

supercoe wrote:Many routers do not support NAT loopback, without this feature you will not be able to connect to "ABCXXX.dyndns.ws" from within your LAN.

Try using http://www.yougetsignal.com to check if you opened the ports for UltraVNC correctly or try from a computer outside of your LAN.
Would this specific to UltraVNC? I ask because I have used this router successfully with pcAnywhere and teamviewer. With pcAnywhere I had to open several ports but after that it worked fine. teamviewer worked fine without any router changes...
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supercoe
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Re: Local LAN works but not WAN

Post by supercoe »

But did you use a PCAnywhere viewer from within your LAN to connect to ABCXXX.dyndns.ws?

TeamViewer will always work as they use a mediating server so both the viewer and server make outgoing connections. Port forwarding isn't needed in this case but it will be a much slower connection when you are on the same LAN.

You have not stated if www.yougetsignal.com shows that your VNC ports are open when the VNC server is running....
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FMinMI
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Joined: 2010-12-14 23:24

Re: Local LAN works but not WAN

Post by FMinMI »

supercoe wrote:But did you use a PCAnywhere viewer from within your LAN to connect to ABCXXX.dyndns.ws?

TeamViewer will always work as they use a mediating server so both the viewer and server make outgoing connections. Port forwarding isn't needed in this case but it will be a much slower connection when you are on the same LAN.

You have not stated if www.yougetsignal.com shows that your VNC ports are open when the VNC server is running....
On my home computer I set up pcAnywhere as a HOST which ran every time that computer started up. Then on my laptop I would startup pcAnywhere REMOTE which said to connect to ABCXXX.DYNDNS.WS (since I don't have a static IP). It would connect fine, ask for user ID and password, and I was in. I did have to open one TCP (5631) and 2 UDP ports (22,5632) in the APPLICATION RULES and PORT FORWARD sections on the router to make it work (pointing it to my LAN static IP address of 192.168.0.2). I did not have to do anything special with Norton Internet Security -- it apparently set access for this program automatically from a firewall standpoint.

Yesterday I removed UltraVNC and installed teamviewer on both computers. It is working fine without ANY changes but would prefer to get UltraVNC to work if I could -- teamviewer is a little more difficult to use and always leaves an 'announcement' saying you are using a free version. But if I cannot figure out what is worng, I will have to stay with it.

BTW, I did go to the website you mentioned and tested a bunch of ports that I know are forwarded. It said all were closed even though I went to the router and confirmed them open. I am not sure what is going on there. I then ran the SCAN ALL PORTS but it said none were open. I am going to try it again after turning off NIS 2011 and the local firewall.
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Re: Local LAN works but not WAN

Post by supercoe »

Make sure the UltraVNC server is running when you do a port test. Seems like your router isn't setup correctly.

You still haven't stated whether your PCAnywhere remote and home computer were on the same LAN when you connected using the dyndns address.

I believe that the issue is because your router doesn't support NAT loopback, this means that you will not be able to use a WAN address (dyndns) to connect to a computer on the same LAN.

Teamviewer is not relevant in these tests because it uses a mediating server so both computers are making an outgoing connection to Teamviewer therefore bypassing the firewall. AFAIK Teamviewer can also detect that both computers are on the same LAN and make the connection locally.
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FMinMI
Posts: 5
Joined: 2010-12-14 23:24

Re: Local LAN works but not WAN

Post by FMinMI »

supercoe wrote:Make sure the UltraVNC server is running when you do a port test. Seems like your router isn't setup correctly.

You still haven't stated whether your PCAnywhere remote and home computer were on the same LAN when you connected using the dyndns address.

I believe that the issue is because your router doesn't support NAT loopback, this means that you will not be able to use a WAN address (dyndns) to connect to a computer on the same LAN.

Teamviewer is not relevant in these tests because it uses a mediating server so both computers are making an outgoing connection to Teamviewer therefore bypassing the firewall. AFAIK Teamviewer can also detect that both computers are on the same LAN and make the connection locally.
OK. I did not have the server running. When it is running, port 5900 is open.

With pcAnywhere, I connected both from my LAN and WAN (when I was on a totally different internet connection).

So, knowing 5900 is open I went to ADMIN settings in UVNC and clicked off AUTO and set Main port to 5900. I then tried to again connect to ABCXXX.dyndns.ws AND when that did not work, put in the actual IP address. Neither worked. Yet if I use 192.168.0.2, it works.

I did try some other options in ADMIN settings such as allow loopback but no good.

My router is quite new -- DLINK DIR 655 and has many features. I would be surprised if it did not allow UltraVNC to work. BUT are you saying it might work if I took my laptop to McD and try to connect from there, even though I cannot connect from within my LAN by going 'out to the internet' first?

Thanks again for your suggestions.

Frank

UPDATE: Went to MacDonalds to use their free wifi. I CAN get into my home computer via both direct IP address and .DYNDNS.WS info. So only issue is the loopback...
Last edited by FMinMI on 2010-12-19 00:54, edited 1 time in total.
FMinMI
Posts: 5
Joined: 2010-12-14 23:24

Re: Local LAN works but not WAN

Post by FMinMI »

supercoe wrote:Make sure the UltraVNC server is running when you do a port test. Seems like your router isn't setup correctly.

You still haven't stated whether your PCAnywhere remote and home computer were on the same LAN when you connected using the dyndns address.

I believe that the issue is because your router doesn't support NAT loopback, this means that you will not be able to use a WAN address (dyndns) to connect to a computer on the same LAN.

Teamviewer is not relevant in these tests because it uses a mediating server so both computers are making an outgoing connection to Teamviewer therefore bypassing the firewall. AFAIK Teamviewer can also detect that both computers are on the same LAN and make the connection locally.
UPDATE: Just found this info doing a google search:

"Just to help anyone in the future...

The D-Link DIR-655 router does support loopback"

http://hardforum.com/showthread.php?t=1257761
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