[dns-operations] Configurable TC=1?

Robert Edmonds edmonds at mycre.ws
Mon Dec 21 18:13:51 UTC 2015

Edward Lewis wrote:
> DJBdns was a popular implementation of the time for this registry.  As
> noted earlier in the threat, DJBdns would not respond to queries for which
> it wasn't authoritative for.  Makes sense.  The result was my probing code
> had to sit out a time-out for the server before deciding it wasn't going
> to answer.  And since the server didn't answer, I was unable to mark the
> run of zones as "lame" because a lame server is only a server that answers
> negatively (for the zone's SOA).  (I did parallelize this, all threads
> quickly hung up on the time-ing servers.)

Not to beat a long gone horse, but if you need to make a large number of
requests, using blocking I/O and a thread-per-connection model for a
connectionless protocol is a really bad idea.  Why didn't you use a
single UDP socket to send queries and process responses as they came in?

Robert Edmonds

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