DNS problems to RoadRunner - tcp vs udp
Seth Mattinen
sethm at rollernet.us
Fri Jun 13 18:24:27 UTC 2008
Jon Kibler wrote:
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> 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.
~Seth
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