DNS Connection Question

dsr at tao.merseine.nu dsr at tao.merseine.nu
Wed Oct 20 09:31:00 EDT 2004


On Wed, Oct 20, 2004 at 09:24:03AM -0400, trlists at clayst.com wrote:
> Simply making a TCP connection on port 53 works well about 98% of the 
> time, but apparently some nameservers are configured to only accept UDP 
> on that port, and those my code currently considers to be invalid, 
> requiring manual intervention.  That's the problem I'm working on.  

Nameservers always try 53 UDP first, because most requests and
responses will fit into a single packet.

You could go to the trouble of constructing your own code, but
why not call "dig" and see if you can get a valid response?

-dsr-



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