wsDualHttpBinding works on LAN but doesn't work on internet - wcf

I have a wcf simple program that use wsDualHttpBinding. I put my server.exe on another computer (on my LAN network) and called a method via client. callback successfully called at client. Then I put my server.exe on my VPS server (on Internet) and run client.exe, client throws TimeoutException.
I use 9090 port for server listening. Also I turn off firewall on both side.
what's wrong?
please help, it's going me crazy.
EDIT:
Do both server and client need valid IP address?

Check your client's config . Try increasing the below settings:
<binding name="WSDualHttpBindingEndpoint"
openTimeout="00:01:00"
receiveTimeout="00:10:00"
sendTimeout="00:01:00"
Verify that the Service Operation is being called & is returning in a timely fashion.
Have Service write to log when method is entered & exited.
Also verify port 9090 is not blocked.

Try to publish http metadata with metadata endpoint in your server.exe and open webservice page on client machine in browser.
I also recommend you to use nettcpbinding instead of wsDualHttpBinding even over the Internet because it's more stable, persistent channel and AFAIK wsDualHttpBinding requires two ports for normal duplex conversation (see ClientBaseAddress in client binding). Tcp needs one though

The problem has solved!
In duplex connections, both client and server need valid ip address.
I changed connection way. I used netTcp.
anyway tnx everyone.

Related

wsDualHttpBinding ClientBaseAddress & firewalls

I'm planning on using a wsDualHttpBinding for a WCF service with callbacks. The clients will be a windows form application communicating to the service over the internet. Obviously I have no control over the firewall on the client side, so I'm wondering what is the proper way to set the ClientBaseAddress on the client side?
Right now in my intiial testing I'm running the service and client on the same pc and i am setting the binding as follows
Dim binding As System.ServiceModel.WSDualHttpBinding = Struct.Endpoint.Binding
binding.ClientBaseAddress = New Uri("http://localhost:6667")
But I have a feeling this won't work when deploying over the internet because "localhost" won't translate to the machine address (much less worrying about NAT translation) and that port might be blocked by the clients firewall.
What is the proper way to handle the base address for callbacks to a remote client?
some one tell me if i do not specify ClientBaseAddress then WCF infratructure creates a default client base address at port 80 which is used for the incoming connections from the service. Since port 80 is usually open to firewalls, things should just work.
so just tell me when win form wcf client apps will run then how can i open my custom port like "6667" and also guide me what library or what approach i should use as a result response should come from client side router
to pc and firewall will not block anything. please discuss this issue with real life scenario how people handle this kind of situation in real life. thanks
The proper way is to use TCP transport instead of HTTP transport. Duplex communication over HTTP requires two HTTP connections - one opened from client to server (that's OK) and second opened from server to client. This can work only in scenarios where you have full control over both ends. There is simply too many complications which cannot be avoided just by guessing what address to use like:
Local Windows or third party firewall has to be configured
Permission for application to run - listening on HTTP is not allowed by default unless UAC is turned off or application is running as admin. You must allow listening on the port through netsh or httpcfg (windows XP and 2003) - that again requires admin permissions.
Port can be already used by another application. In case of 80 it can be used by any local web server - for example IIS.
Private networks and network devices - if your client machine is behind the NAT the port forwarding must be configured but what if you have two machines running your application on the same private network? You cannot forward from the same incoming port to two machines.
All these issues can be avoided mostly only when you have control over whole infrastructure. That is the reason why HTTP duplex communication is useful mostly for intranet scenarios and why for example Silverlight offers another implementation where the second connection is not created and Silverlight client instead polls server continuously to check if there is any callback available.
TCP transport requires only single connection from client to server because TCP protocol is natively duplex so the server can call back the client through the same connection. When you deploy a public service you usually have control over infrastructure on the server side so you can make necessary changes in configuration to make it work.
I think this also answers your previous question.

WCF No connection could be made because the target machine actively refused

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.

wcf service port

I have two processes running on the same machine. Each process is hosting a WCF service to allow inter process communications asynchronously. As of now, I have assigned a fixed port 8731 and 9000 to the two wcf services. What if a customer machine has these ports taken up? How can i dynamically make the wcf client find the wcf service if I were to dynamically allocate an available port?
Thanks for your help in advance.
I assume you're creating services in code. If you're afraid of the client not having those ports available, you should configure your endpoints using app.config. That way, if a client has an issue with a port, you can simply change their config file instead of recompiling your code.
I am late on this post, but today we have better solution for this problem.
There is a configuration endpoint known as listenUriMode(https://msdn.microsoft.com/en-us/library/system.servicemodel.description.listenurimode(v=vs.110).aspx), if we set this value to "Unique", it will bind hostname to port 0 which will ask OS to assign a free port.
Now client can know about the server port using WCF discovery(https://learn.microsoft.com/en-us/dotnet/framework/wcf/feature-details/wcf-discovery-overview).

Connection refused - nettcp WCF Service from work - client connecting over VPN

Here's the scenario: A client machine has connected to the 'Work network' via VPN (Cisco VPN Client). The work network hosts a machine that has a WCF service with nettcp binding. The client tries to connect to this service and gets an exception as follows:
Could not connect to
net.tcp://workMachine:2010/SomeService.
The connection attempt lasted for a
time span of 00:00:01.3180754. TCP
error code 10061: No connection could
be made because the target machine
actively refused it workMachine:2010.
Things I tried:
Changed the Workgroup of the client
machine to the work network
workgroup
Added domain/username/password for the Windows Networking Password vault, so that it can be used to connect
Changed the wcf service path with an IP address instead of the workMachine name
Checked client machine firewalls and added to allow the wcf client through it
All above failed and didn't work.
Has anyone encountered similar issues?
The client machine is on Windows 7
SecurityMode of the WCF service is set to NONE - so that shouldn't be an issue.
Any insights will be helpful
You may need to supply client credentials explicitly through your proxy object.
Assume that the proxy object in the code below implements one of the ClientBase interfaces.
proxy.ClientCredentials.Windows.ClientCredential.UserName = "clientaccount";
proxy.ClientCredentials.Windows.ClientCredential.Password = "S3cr3t1337Pwd";
Could you - just for testing purposes - expose the same service on the same machine using a HTTP endpoint, and try to connect to that one from your VPN client?
NetTcp is an excellent choice behind the corporate firewall - just don't know how the Cisco VPN client might cause troubles here, that might not show up when using an http-based protocol. Just a wild guess for now, but if you have nothing else to go on, give it a try!
Marc
Just another thought to assist with debugging of these kind of issues, using CMD execute "netstat -a" (you can append the -o switch and find the related process id also) and see if the port in question is currently open, if it isn't you may have an issue with the SMSvcHost.exe (this is the Windows process for managing an IIS hosted TCP Service).
I've had this issue before and rectified it by restarting the following services (obviously you'll need to carefully consider this if you are dealing with a live production system):
NetTcpActivator (Net. Tcp Listening Adapter)
NetTcpPortSharing (Net. Tcp Port Sharing Service)
and possibly if relevant:
NetMsmqActivator (Net. Pipe Listener Adapter)
NetPipeActivator (Net. Pipe Listener Adapter)
Hope this helps someone!
J.

WCF + SSL wsDualHttpBinding or netTcpBinding

I need to create a self-hosted WCF service.
I need secure duplex connection between client and server through Internet.
I read some documents of WCF and found that the netTcpBinding is suitable for intranet application, because the SSL is only point 2 point. If it is an internet application, the connection must not be point 2 point, am I correct? so SSL in transport security with netTcpBinding is not suitable?
so what combination should I use to create a secure duplex internet application?
thank you very much.
I have tried http://www.codeproject.com/KB/WCF/WCFWPFChat.aspx
this tutorial use netTcpBinding and endpoint localhost
I change the endpoint localhost to a name based url, forward a port in my router to my development PC, open the same port at Windows firewall.
The client program can chat with each cients program in different machines, BUT the callback connection will lost after one minute.
I also tried changing the binding to wsDualHttpBinding, the clients program can chat with each clients in the same machine and kept the callback connection in the reliableSession inactivityTimeout setting. However another client program in another machine cannot join the server, if I turn off Windows firewall on that machine, the client program can connect.
It seems that tcp binding can let the client program connecting to the server with Windows firewall turn on. but callback connection lost.
and the wsDualHttpBinding can keep the callback connections. but cannot connect to server if Windows firewall on.
Is there a way to kept the netTcpBinding callback connection as in the wsDualHttpBinding?
It sounds like you have two issues- duplex connection and security.
If you truly need a duplex connection (eg, server-initiated callbacks), neither of these will work very well over the internet unless you have very fine control over the firewalls on both ends (the client still has to expose a publicly accessible HTTP endpoint for the server to call back). The best way would be to use the new relay services with .NET 4.0- this allows for a mimic'd server-initiated connection through firewalls.
EDIT: this is now called AppFabric, and is part of the Windows Azure infrastructure
On the security front, you can always use message security over the service bus, but I don't see a reason why transport security would be a problem either.
To answer user248724,
The client program can chat with each
cients program in different machines,
BUT the callback connection will lost
after one minute.after one minute.
You need either have the client or the server to ping each other at least every minute to keep the connection socket alive.