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I moved our web hosting to Amazon EC2. At first everything was working well. In the last few days I have been getting this error:

The requested name is valid, but no data of the requested type was found

This seems to be a DNS issue, and I have no idea how to deal with this.

Has anyone seen this error from an EC2 instance?

More Info: It is a windows instance. The look up is a reverse look up of the current machine. The callstack looks like this:

     SocketException (0x2afc): The requested name is valid, but no data of the requested type was found]   
    System.Net.Dns.InternalGetHostByName(String hostName, Boolean includeIPv6) +7987115   
System.Net.Dns.GetHostAddresses(String hostNameOrAddress) +544   
ClientDependency.Core.UriExtensions.IsLocalUri(Uri uri) +184
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Where and in what context are you getting this error? Do you know what name is being requested? If you think it is a DNS issue, what is your server's DNS configuration? Would you care to tell us whether this is a Linux instance or a Windows instance? Unfortunately, your question in its current/original form is not answerable. – Skyhawk Mar 30 '12 at 8:01
Added more info. Sorry, I was thinking maybe this is a known issue with AWS. This worked on a VPS hosted with GoDaddy for a year without error, before moveing to AWS. – Elad Lachmi Apr 2 '12 at 1:10
Possible duplicate:… – Skyhawk Apr 2 '12 at 1:43
@MilesErickson - 1. Not really. 2. This is a system issue, not a c# issue, since it started only after moving to AWS, and with no code changes. 3. Last, but not least: There is no answer there :) – Elad Lachmi Apr 2 '12 at 1:53
If it worked at first, then I sincerely doubt that this is directly related to your move to EC2. The link to the duplicate question was for future reference/moderation purposes, not because I thought it would be immediately helpful. – Skyhawk Apr 2 '12 at 2:03
up vote 2 down vote accepted

This is a Windows issue that is not specific to Amazon EC2.

Others who have experienced this error message have reported resolving it in the following ways:

  • Simply rebooting the server
  • Resetting the Windows TCP/IP stack with netsh int ip reset
  • Modifying the ASP.NET application's source code: Example 2
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