Q227943: How IIS Handles Reverse Lookup Failures

Article: Q227943
Product(s): Internet Information Server
Version(s): winnt:4.0
Operating System(s): 
Keyword(s): 
Last Modified: 04-FEB-2000

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The information in this article applies to:

- Microsoft Internet Information Server 4.0 
- Microsoft Internet Information Services version 5.0 
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SYMPTOMS
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IIS can perform access restrictions based on IP address, IP range, and DNS name.
If you are performing IP restrictions based on the DNS name, it requires that
IIS perform a reverse DNS lookup. If reverse DNS lookup fails (for example
failure to access the DNS server) then the request is refused.

MORE INFORMATION
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Note: You may need to restart IIS in some instances if the reason for the lookup
failure is corrupted DNS entries.

Additional query words:

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Keywords          :  
Technology        : kbiisSearch kbiis500 kbiis400
Version           : winnt:4.0
Issue type        : kbprb
Solution Type     : kbpending

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