On May 15, 2008, at 7:59 PM, Filipe Brandenburger wrote:
Not true (AFAIR). If I remember correctly, if the information about the destination of the CNAME is on the same DNS server (either because it is authoritative, or because the resolver has it already on cache), it will piggyback the information on the same response packet. You can check this behaviour by using "dig" with the options that show all that comes in the original response.
Yes, you are correct.
I was mis-remembering this bit of RFC 1035 about restarting the query: "CNAME RRs cause no additional section processing, but name servers may choose to restart the query at the canonical name in certain cases. See the description of name server logic in [RFC-1034] for details." --Chris