DNS problems to RoadRunner - tcp vs udp

Seth Mattinen sethm at rollernet.us
Fri Jun 13 18:24:27 UTC 2008

Jon Kibler wrote:
> Hash: SHA1
> Mark Price wrote:
> <SNIP>
>> >From what I have read, public DNS servers should support both UDP and
>> TCP queries.  TCP queries are often used when a UDP query fails, or if
>> the answer is over a certain length.
> UDP is used for queries.
> TCP is used for zone transfers.
> If my server responded to TCP queries from anyone other than a secondary
> server, I would be VERY concerned.

I see long TXT records from some DNSBLs that won't fit in a UDP packet 
on a daily basis. Certainly nothing to be concerned about.


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