I am writing an application with C++ to connect to my server.
I am using gethostbyname(). It is working fine when I give host name as 'localhost'. but if i try any other site like google.com, it fails.
Can anyone please tell me what could be going wrong.
I can access those websites through browser. Note: I have proxy set up in my browser.
Is thr proxy causing issue with gethostbyname()? if yes, how can I mention proxy in my C++ code?
Based on what you describe in your question, it appears that your machine is on a corporate network that is firewalled off the Internet, all access to the web is via a web proxy, and that your network does not have Internet DNS resolution.
Even if you managed to succeed in resolving an IP address, you will not be able to make an outbound connection, unless your firewall offers a Socks proxy, or an equivalent.
If your intent is to write a client that accesses web sites via HTTP, you will need to use your corporate HTTP proxy to do that. Contact your system administrator for more information.
Related
How can i host a website through my computer using server softwares?
I tried to host a website through my own computer using apache tomcat server but it didnt work ( please briefly explain every point )
The main issue that you need to deal with is getting the clients to your computer.
Yes, it is possible and yes I have done it, albeit a while ago.
You need to see if you can browse to your computers website from another device on your network, this will ensure that apache is working. Try another computer/laptop/tablet/whatever to see if this site reachable by other computers using the IP Address and possibly port number. If you cannot get to the site, there are settings in apache to deny certain ip's, google it to get the exact steps for your version. If it works, move on to step 2.
You will need a static IP Address to ensure that all further steps stay working, google this if you are not sure how to do it
You need to have the external IP address of your router(whatsmyip.org) or use Dynamic DNS to route traffic from an address to your ip and there are services that allow this. I can recommend no-ip.com - This is all assuming that you have access to the router.
You would be required to set up port forwarding on your router. This will direct the internet traffic to your computer. You will need to get the exact instructions for your specific model of router.
Please be aware that you need to have proper firewalls and systems in place to prevent attacks. I am sure that you are just testing at this point though...
All the best!
I have a server written on C++ REST SDK.
There's http_listener which listens to "http://localhost:34568".
When I try to send a request in browser or from the client to localhost it works fine and I get the responses from my server. But the point is to use the application in network. And here where the problem comes.
When I try to request the server from the other PC using IP(192.168.1.103:34568) I get "HTTP Error 400. The request hostname is invalid."
I'm aware that that could be some firewall issues but it's turned off. Also I tried to set port rules in brandmauer and it didn't help.
And even more! I got XAMPP running Apache server and when I do the same thing but with (192.168.1.103:80) I do get the response from Apache and have an access.
Anybody had something similar or somebody knows what the problem is about?
Listen to local ip address or to your network name (dns):
"http://xxx.xxx.xxx.xxx:34568" or
"http://your_network_name:34568"
So, if you have multiple network adapters, you can choose which one.
We have created self-hosted services using OWIN. They are working fine inside the server and we can request and retrieve information using the http://localhost. We use a different port for each service so that we can go and get certain information from http://localhost:8001, other from http://localhost:8015 and so on.
Now, we need to expose the results of one of those self-hosted services to access to it through internet. We'd like to provide a custom address such http://ourpublicinfo.mydomain.com:8001 or using the server ip such http://209.111.145.73:8001.
Is that possible?
How can we implement it?
Our server OS is Windows Server 2012 R2
OWIN Self-Hosted apps can run on a Windows Service, as a Console process and, with if desired, as part of a more robust Host like IIS.
Since you mention your app is running as a service you're probably missing all the GUI goodies IIS provides. In reality however, IIS works on top of http.sys, just as HttpListener does (which is probably what you're using to self-host your app) 1. You just need to do some manual set up yourself:
First of all, you need to make a URL reservation in order to publish on a nonstandard port.
Why would you do that? Quite simply because you're not running under localhost alone anymore on your very own local machine, where you probably are an admin and/or have special privileges/powers.
Since this is a server, and the user used for running the Service might not be an admin (most probably), then you need to give permission to that user to use that URL... and here is where URL reservations come into scene.
You pretty much have to options:
open up the URL to be used by any user:
netsh http add urlacl url=http://209.111.145.73:8001/ user="everyone" listen=yes
or open up the URL to be used by the user(s) running the service, e.g.: NETWORK SERVICE:
netsh http add urlacl url=http://209.111.145.73:8001/ user="NETWORK SERVICE" listen=yes
There is a way to make the reservation for several users too, using sddl, user groups, etc... but I'll not get into it (you can look that up).
Second of all, you need to open up a hall through your firewall (if you don't have one on this day and age, I pity you!)
There are plenty of tutorials on this. You can use a GUI, netsh.exe and what not.
Pretty much all you need to do is make sure you allow incoming connections through that port and that should do the trick.
To make sure the hall is open through and through you can use a tool like http://www.yougetsignal.com/tools/open-ports/ and insert 209.111.145.73 in the Remote Address and 8001 in the Port Number.
If for some reason it shows that the port is closed, even after creating an incoming rule in your firewall for it, then you probably have one or more firewalls in between your server and the outside world.
With those to elements in place you should be able to access your Self-Hosted Service from the outside.
As for accessing your service through an address like http://ourpublicinfo.mydomain.com:8001, you'll need to create a DNS entry somewhere, most likely on your Domain Registrar for mydomain.com, where you could create an A Record for your ourpublicinfo subdomain pointing to 209.111.145.73.
From this point on, you should be able to access your service through direct IP and Port or through the afore mentioned URL.
Best of luck!
Note:
If your service will be access from other domains, you might need to make sure you have CORS (Cross Origen Resourece Sharing) well defined and working on your service too ;)
I have been asked to take over a project where the previous developer had used socketio4net,
hence I learnt of the socketio4 project only now.
the problem my employer is facing is clients having proxy servers.
we have installed our product(client side) on clinics which uses socketio4net and websocket.
They all connect to our main azure server for sending data. In clinics without proxy,we are not facing any issues. but those with proxy server, our service is not even starting.
if we have to implement the ssl process, it will be a big overhead for us
how do we achieve ssl and proxy settings for sockets in general? does socketio4net provide any other options?
do I have change to http classes like webclient?
In my experience with proxies and school's in particular, the vast majority turned out to be a firewall based issue.
What port are you using, 80, 443 or something else? If that is the issue, the clinics would need to either whitelist your server ip, or allow the ip:port combo you've set.
For a quick test at the clinics that have issues - I would try these two sites (probably others sites you can find too):
http://websocketstest.com/ - tests for ports 80, 8080, 443 with and without ssl - do all or only some work?
(this site is also great for a end-user at the site to run for you, as you can get a results link - double bonus points!)
http://www.websocket.org/echo.html
Are both of the sites above able to connect?
Hope that helps...
Im just wondering, can 2 or more different external hostname/DNS redirect to multiple local servers but same port?
Let's see, I have 2 DNS internet domain for an example, myserver1.com and myserver2.com, and both I have same A record to my forwarded server IP (e.g: 102.123.123.123). Under my server which only has 102.123.123.123 IP address has 2 application servers but instead of trying to make they work, I use different port for each server applications for an example, serverApp1 listening to 0.0.0.0:2010, serverApp2 listening to 0.0.0.0:2020
My point is, is there any way or how to forward my myserver1.com:2000 to serverApp1 (port 2010), and myserver2.com:2000 to serverApp2 (port 2020) but both myserver1.com and myserver2.com has a same A record?
Im quite sure either it is in iptables or /etc/hosts or BIND issues, but guide me if I missed something. And by the way, the servers and DNS records are accessible from the internet which is the firewalls are configured properly. Thanks.
I don't have much experience in that, but I think you will need a third server/firewall/proxy listening for the incoming host and route it accordingly.
Again, I don't have much experience in that, so I'm not sure if the firewall is able to do that.
I think you can use redirection servers like apache.
In my application we want to access lot of intranet servers from internet. So what we did, we configured a apache with all the mappings in httpd.
So when ever a request to apache comes, it will be redirected appropriately.
For example - I have two servers or hostname in intranet : 1) abc.com:7300/context1
2) xyz.com:8900/context2
We configured a apache with host name abcxyz.com:9000. When a request like
abcxyz.com:9000/context1 comes it will be redirected to abc.com:7300/context1 and when a request like abcxyz.com:9000/context2 comes it will be redirected to xyz.com:8900/context2.
In your case since the requests are going through the single server (102.123.123.123), you can use redirection.
Hope it helps.