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DaveCast? What??
By Dave Winer on Wednesday, June 22, 2011 at 11:12 AM.

In a conference call yesterday I said I'd do a podcast more regularly. Permalink. #

So here's the first installment of what I'm calling DaveCast for lack of a more imaginative name.  #

BTW, my revelation for the day is Negative Time To Live, which is part of the DNS protocol. Until yesterday I didn't know it existed. I assumed that every time I do a DNS lookup I get a fresh bit of data from the authority on the name. I didn't know that servers could cache the negative result.  #

But, I don't think negative results should be cached. Why would I be repeatedly asking for the definition of a name that you just told me was undefined? I must have some idea that it should be defined.  #

Maybe I defined it. :-) #

Amazon, in Route 53 provides a way to query the status of a request to create a new record. Usually it takes 5-7 seconds for a DNS request to go from pending status to insynch status. So I made the Blorkmark request be synchronous. It doesn't return until Amazon says it's defined. Then I do a DNS lookup. It works, and we're ready to roll.  #

Seems DNS itself should be able to handle it. Amazon doesn't really know if the domain will resolve, it just thinks it will. DNS is authoritative.  #

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