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Java Viewer via ASUS W-Fi Router connection problem

Should you have problems with the JavaViewer, here's the place to look for help or report issues
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Moriarti
Posts: 1
Joined: 2009-03-31 02:36

Java Viewer via ASUS W-Fi Router connection problem

Post by Moriarti »

I'm want to connect to my home computer from work.

I have installed UVNC server Version 1.0.5 on the Home machine and remap port 5800 like in

"Port forwarding NAT/router/firewall for any VNC flavor"
[topic=3859][/topic] instruction:

incoming from WAN to LAN
port 5800 TCP protocol --> ip/hostname --> winvnc http VNC server http

but if I try to connect:

http://myhost.domain.com:5800
myhost.domain.com - is a static ip adress from provider.

I get a request to accept the certificate (which I do), Java applet loads and displays my computer name but then nothing is displayed in the browser: window with query password () does not apear...

- At client side, I am running Java version 6 patchlevel 11.
- When I am connect from local home network - http://192.168.4.2:5800 - All Ok.
- dsmplugin not use!
- firewall is off.
- On my work interner through http proxy.

I'm found similar question:
[topic=11664][/topic]

Is is right for Java Viewer?

1) UVNC Server using 5900 (VNC) and 5800 (Java)
2) When a connection is made from a client to the Java Viewer (via a web-browser) on port 5800 the applet is downloaded to the client and run locally.
3) The Java-Viewer then makes a (VNC) connection to the server on port 5900
YY
200
200
Posts: 996
Joined: 2006-11-13 15:11

Re: Java Viewer via ASUS W-Fi Router connection problem

Post by YY »

Moriarti wrote:Is is right for Java Viewer?

1) UVNC Server using 5900 (VNC) and 5800 (Java)
2) When a connection is made from a client to the Java Viewer (via a web-browser) on port 5800 the applet is downloaded to the client and run locally.
3) The Java-Viewer then makes a (VNC) connection to the server on port 5900
Yes, the statements are correct.

And what you need to do is forward BOTH 5800 & 5900 TCP to UVNC server pc.
jksmurf
20
20
Posts: 56
Joined: 2006-05-24 02:30

Re: Java Viewer via ASUS W-Fi Router connection problem

Post by jksmurf »

How does this work if I have chosen different port forwards for UVNC and UVNCJava.

e.g. normally you'd go

1. Internal/External UVNC Java = 5800=>5800 = Server IP XX.XX.XX.XX
2. Internal/External UVNC = 5900=>5900 = Server IP XX.XX.XX.XX

So that e.g. you'd use http://no-ip.com.mypc:5800 and it would work because 5800 and 5900 are both known to be needed.

But if my router is set up to forward

1. Internal/External UVNC Java = 801=>5800 = Server IP XX.XX.XX.XX
2. Internal/External UVNC = 901=>5900 = Server IP XX.XX.XX.XX

you'd use http://no-ip.com.mypc:801.

However when I use that, I get through to the PC as it resolves the host name (at least I assume for 801) but all I get is a blank screen? How does it (would it) know to use 901? Or MUST I use 5800/5900 ONLY with JavaViewer, no other ports are available?

(Checked Firewalls are OK, they let 5800, 5900 through. 801 & 901 are external so they map to 5800/5900 internal)

Thanks!

k.
YY
200
200
Posts: 996
Joined: 2006-11-13 15:11

Re: Java Viewer via ASUS W-Fi Router connection problem

Post by YY »

Basically your understanding is correct, and also you are free to choose any port other than 5800/5900.

The problem is that: when using JAVA connection, after the initial stage using JAVA port (5800 default), the final connection will switch to main port, AND BASE ON ITS SETTING, THE UVNCserver WILL INFORM THE REMOTE VIEWER THIS NEW PORT NO. In your setting, the server will ask the viewer to switch to 5900.

So in your case,
- the initiate stage, HTTP Browser ==>801 ==> 5800 (Server), OK
- VNCserver asks viewer to use 5900 for further communication,
- JAVAviewer switch to 5900 ==> (Blocked by the firewall)


The solution:
If you want to use 801/901 externally, then you must configure the server to use main port 901, AND your router must forward 901 ==> 901 (Server IP)
Last edited by YY on 2009-04-29 04:23, edited 1 time in total.
jksmurf
20
20
Posts: 56
Joined: 2006-05-24 02:30

Re: Java Viewer via ASUS W-Fi Router connection problem

Post by jksmurf »

YY,

Thanks very much for taking the time to compose such a clear answer. I can't wait to get home to try it, it has been driving me crazy for ages. I have tried numerous combinations with no result.

Thanks again, will let you know how I get on.

Cheers

k.
Last edited by jksmurf on 2009-04-29 08:00, edited 1 time in total.
redge
1000
1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Re: Java Viewer via ASUS W-Fi Router connection problem

Post by redge »

best solution is go back to single port for both service.
only 1 port in use.
was available before but removed.
va savoir Charles.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
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