I have a .NET program running on Ubuntu via Mono 2.10

The program downloads a webpage via an HttpWebRequest every minute or so which works fine most of the time:

        String result;
        WebResponse objResponse;
        WebRequest objRequest = System.Net.HttpWebRequest.Create(url);

        using (objResponse = objRequest.GetResponse())
        {
            using (StreamReader sr =
               new StreamReader(objResponse.GetResponseStream()))
            {
                result = sr.ReadToEnd();
                // Close and clean up the StreamReader
                sr.Close();
            }
        }

The problem is that after few days I start getting exceptions thrown:

        DateTime: 01/25/2012 08:15:41
        Type: System.Net.WebException
        Error: Error: NameResolutionFailure
        Stack:
          at System.Net.HttpWebRequest.EndGetResponse (IAsyncResult asyncResult) [0x00000] in <filename unknown>:0
          at System.Net.HttpWebRequest.GetResponse () [0x00000] in <filename unknown>:0
          at socks_server.Program.readHtmlPage (System.String url) [0x00000] in <filename  unknown>:0
          at socks_server.Program.getAccessKeysProc () [0x00000] in <filename unknown>:0

The server is still abel to resolve DNS, for example

 wget http://www.google.com

Will return the file without any probelm as will ping and other commands that resolve DNS.

My program however will continue to throw that exception until I restart it. After restarting the application it will start working again as it should.

I have checked open file counts on the system (400 ish), memory usage (327mb of 4gb), CPU usage (2-3%) and all are OK.

Any ideas?

c# ubuntu mono httpwebrequest
Edit
Report