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

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.