I built a WCF service that exposes itself for a web application, it accepts an object and prints the data on the clients machine. Works fine on my development machine, and the service is up and running on any machine i install it on. I can enter ip address in clients machine web browser and see it is running. Problem is when i send the object to the clients machine it returns an error, that sounds like it could be because of the clients windows firewall. Where would i start at to deal with this problem ?
There was no endpoint listening at http://192.168.1.168:2202/PrintLabel that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException, if present, for more details.
And the InnerException: Unable to connect to the remote server
With further research and discussion with people in the community i came to understand that as was mentioned at the bottom of this article.
"Self-hosted HTTP addressing for WCF is not integrated into the Windows firewall. An exception must be added to the firewall configuration to allow inbound connections using a particular URL.
But this SO question led me to a page with how to control Windows Firewall through code to enable my WCF self hosted service to accept an object.
This the link below.
http://www.shafqatahmed.com/2008/01/controlling-win.html
That link was towards the direction i needed, but based on user comments it seemed to have some bugs. A colleague found this link and i believe this technique will be the best solution for this scenario.
Related
I've got a working WCF service and a working Delphi client. On a normal PC, they work nicely. On a VM that's "Bridged" they work nicely if I log onto the domain (but not if I logon locally to the VM as administrator). If the VM is NATed, the connection attempt times out.
I would love to hear people's thoughts on what could be making such a difference to whether the client can successfully connect to the WCF service. Bear in mind I'm connecting with basicHttpBinding with no security.
The service is setup to use System Account (interact with desktop is NOT checked), and it starts automatically. The service URI doesn't change, the port is open, and can be telnet'd to in all scenarios.
Any ideas or pointers?
Within the VM, open Internet Explorer and verify that you can view the WSDL of the WCF service. If you can't, then your issue is connectivity and has nothing to do with your Delphi code.
Group Policies and Enterprise Security solutions that swap certificates or require certificates to be registered (we're using a UTM called CyberRoam) make a difference.
Also when Virtual Machines join a domain, their ComputerNames are added to a list maintained by the Domain Controller. When the same Virtual Machine is "moved" or "copied", its ComputerName should be changed to avoid DNS resolution issues.
I'm not claiming this as the definitive answer, however it does explain the issues I noticed in this instance.
I just implemented a simple WCF server using net.tcp.
First, I use 127.0.0.1 as server address and client able to connect the WCF service.
Everything is Ok. But when I try to use the internal IP 192.x.x.x I get an error:
No connection could be made because the target machine actively refused it
Any idea what may cause this?
Best Wishes
PS: I disabled auth on WCF. Even turn off firewall all...Not worked...
Well, I got this error message when I forgot to install necessary components. see link Configuring WCF Service with netTcpBinding
(summary of steps)...
Go to "Programs and Features" (usually in control panel)
Go to "Turn Windows features on or off"
(assuming VS2012) Go to ".NET Framework 4.5 Advanced Services"->"WCF Services"
Enable "TCP Activation"
Do you use 192.x.x.x on both client and server? I remember seeing an issue a while back in which for TCP the client and server names needed to match (something related to one of the message properties), so if you define the service with "localhost" and the client with <machine name> there would be a problem.
The physical client and service addresses can differ if the logical address is the same and the server endpoint has been configured with a "listenUri" and the client behaviour is configured to use a <clientVia> address. In our case, this is required in for our proxy/firewall configuration. In effect, the client calls the firewall and the server listens locally for a forwarded request.
For an IIS-hosted service, check the following:
The Application pool is started and looks correct (.NET 4 etc/security)
For NET.TCP, ensure the "Allowed Protocols" in the Web Site/Application (via advanced settings) are configured correctly: e.g. http,net.tcp
For a non-IIS hosted service, you may need to configure a Namespace Reservation (URLACL). http://msdn.microsoft.com/en-us/library/ms733768.aspx
Also ensure the appropriate Windows Services are running, e.g. Net.Tcp listener.
If you're running from within visual studio in debug mode, ensure your solution port numbers match. I have seen several instances where I had Properties>Web>Auto-Assign Port - selected and the endpoint from, in this case my silverlight app, didn't match the port auto generated. I usually change the port to 1318 in my .web.
Today I found out that this error will also show up if you have a circular reference in your WCF Service Class. I had a method that was calling itself infinitely and causing this error message, which led me here.
So if none of the other suggestions work, check your code to see if you're doing any recursive functionality and make sure you're not caught in an infinite loop.
I resolved this issue by either commenting this setting in the application configuration:
<defaultProxy>
<proxy bypassonlocal="False" usesystemdefault="True" proxyaddress="http://127.0.0.1:8888" />
</defaultProxy>
or, running Fiddler which would take the WCF call at 127.0.0.1 and then forward it.
The complete scenario is, I encountered the same issue with WCF calls made to one of the service. The calls would fail with top level error message "There was no endpoint listening at http://LinuxIP:Port/...", and service trace viewer log showing inner exception to be "No connection could be made because the target machine actively refused it 127.0.0.1:8888
".
The reason was that I had put this configuration in my application to capture the outgoing traffic in Fiddler. If this configuration is in place then the Fiddler needs to be running for the WCF calls to make it to the intended destination. If Fiddler is not running this error will be there. Comment this setting in such scenarios, and the WCF call will go to the destination.
I am consuming a web service in .NET application with WCF client.
The Endpoint's address of the service is over port 4338, and it is over HTTPS, secured with WS-Security standard.
So the address is something like :
https://[servername]:4338/[servicename]/
I was not able to communicate to the service with just running the application.
it gave me the following error :
Could not connect to [servername]:4338
TCP error code 10060: A connection
attempt failed because the connected
party did not properly respond after a
period of time, or established
connection failed because connected
host has failed to respond
[servername]:4338
But when I run Fiddler to investigate the http communication, the application start to work, and I will be able to communicate to the service.
As well, I want to add that I have a different service on the same web server that hosts the first service, and that second service's address is hosted on port 8080, and I am able to communicate with it with WCF client (without running Fiddler).
So, I googled and I found that it might be related to the proxy settings. Do you know what the problem is, and how can I solve it?
Thanks
Fiddler acts as an Internet proxy server. In general, any symptom of the form: "it works when I use Fiddler" means "it works when there's a (different) proxy server".
Check your proxy server settings. In particular, as empi suggested, try it in a browser. If it works there, it could be due to the fact that the browser has the proxy settings configured, and that you do not have them configured for WCF.
If you have proxy set in Internet Explorer, it may cause the problem. What happens when you open https://[servername]:4338/[servicename]/ in Internet Explorer?
Thanks empi for the reply.
I found the answer.
Actually in our company we have a proxy settings through "Automatic configuration script"
and depends on the web sites we are targeting internally, the script will point us to the proper proxy.
So, from the script I got the proper proxy address.
and in my .NET application I added this code
WebRequest.DefaultWebProxy = new WebProxy("http://xx.xx.xx.xx:8080");
and that fixed the problem
So WCF client was not detecting the setting of the automatic script.
and this is the reason it worked when I run Fiddler, because Fiddler listen to the http communication, and send it again through the settings.
This is probably a basic networking issue, but I am new to this stuff and just do not know the answer.
I have written a wcf service and client. I can use one of the http bindings and get the service to work correctly when I put my machine's network IP address as the endpoint address and run the client and server from the same machine. Now, I want to be able to connect to this service from a different machine over the internet. Clearly it does not work when I use my network IP address in this scenario, but simply putting in my router's broadband IP address does not seem to be doing the trick, either. Am I just missing a firewall port that I need to open up, or am I trying to do something that should not be possible?
If you want users from the internet to be able to connect to your service, you'll have to consider a few points:
binding: the lowest common denominator is the basicHttpBinding which is SOAP 1.1 with basically no additional features available - just like ASMX webservices. Just about anyone can connect to that. For more advanced clients, you might also want to expose a wsHttpBinding endpoint on your service
security: how (if at all) do you want to secure access to your web service? Do you have username/password credentials that callers must supply? Check out the WCF Security Guidance for a whole slew of information bits on the various security scenarios
authenticating your service: typically, you should strive to make your service authenticate itself to the rest of the world - this requires a server certificate and enables secured communication (messages signed + encrypted) on the wire
make sure your service endpoint(s) is reachable from the internet, through all firewalls and proxies and everything :-)
Hope that helps a bit!
You need to set up port forwarding on your router. Perhaps someone on ServerFault or SuperUser would be able to help you. Or even a google search now that you know what it's called. The instructions will be different depending on the router. The port you need to forward will be the port you've picked in the WCF config file.
I host WCF services through IIS, but it took me ages to work out how. At the moment I put the files on the webserver and enable websharing on the root folder. Then you can assign them to an appropriate Application Pool in IIS, and add a service reference to any client projects using the URL of the wsdl.
I'm not sure if this is the best way to do it but its the only way I've worked out so far.
Here's the simple solution.
I am assuming that you have made a working WCF application and hosted over the IIS.
The next thing to do is to browse the application from the IIS. It will give you url in the address bar something like:
http://localhost/myservice/service.svc
Next go to www.whatismyip.com. this will give you your system's WAN IP (say, 45.34.56.200).
Replace the URL you got in step 2 with: http://45.34.56.200/myservice/service.svc
Now you can use this URL any where in this world to consume your service.
I found a good Article and it is working fine for me, on the following the Main steps:
1-First you should create WCF Service.
2-add application on IIS and give alias for your virtual directory and set path from your local drive.
3-Make sure your default app pool set to .NET CLR V4.0.
4-test your WCF service is running successfully on localhost.
5-To access the same via LAN (Local Area Network) you must disable Firewall for you Private network.
6- try to use ngrok.com, you will get Temp URL to use via internet to access your LocalHost anywhere.
Then Everything will be fine.
For More Information Check the following Link:
https://www.codeproject.com/Tips/813650/Host-WCF-on-LocalHost-and-access-via-Internet
I have a Web application and a WCF service hosted on the same Windows 2003 development server. They each have their own IIS website node responding to drs.displayscreen.web and drs.displayscreen.service host headers respectively. The hosts file contains entries for both headers pointing back to 127.0.0.1. The web site has a service reference to drs.displayscreen.service.
Both applications work perfectly when their application pool uses the 'Network Service' account.
I need to perform some COM processing under the hood on the service so I want to run the applications under a customised identity. Both sites run on a new application pool.
When I change the application pool identity to use a new windows account created for the purpose, I get the following (inner) exception:
[EndpointNotFoundException: Could not connect to http://drs.displayscreen.service/Handler.svc. TCP error code 10060: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 192.168.98.2:8080. ]
192.168.98.2:8080 is the address of a DNS server that is no longer in use. It is not referenced anywhere in the solution. It is not referenced by ipconfig at all.
I have made sure that the new account is a member of IIS_WPG and I have run aspnet_regiis -ga . I have also given the account explicit permission to read the hosts file.
Why does the application attempt to use the defunct DNS server to resolve the temporary url (drs.displayscreen.service) instead of the hosts file entry? It has to be a permission of some sort because it does not have this problem when running under the network service account. Help!!
Well, it appears that the answer might involve a bug in the .Net framework. I found a blog posting that clued me in to the fact that the MS .Net implementation of SocketCache.GetSocket might cache invalid sockets and another one that suggests a workaround/hack in the form of an explicit don't-use-proxies configuration setting.
We don't actually use a proxy server in the environment where this problem cropped up but it appears that SocketCache.GetSocket is overridden or behaves differently when the don't-use-proxies setting is in place. Strangely, removing the setting causes the problem to come back so obviously the SocketCache is not repaired when a valid ip/hostname is discovered and successfully used. According to the author of the first post mentioned above, the bug does not exist in Mono. :)