How many nameservers?

Stephane Bortzmeyer bortzmeyer at
Mon Feb 2 20:44:45 UTC 2009

On Mon, Feb 02, 2009 at 02:25:35PM -0600,
 bsfinkel at <bsfinkel at> wrote 
 a message of 41 lines which said:

> One downside - if you have many NS records, then they might not all
> fit in one UDP packet

Let me demonstrate a bit of pedantism: the correct sentence is rather
"they might not all fit in a traditional DNS UDP packet (512
bytes)". The limit is not UDP's fault. And even with DNS, EDNS0 allows
more than 512 bytes and is now an old technology.

> This will cause the protocol to revert to TCP.

Not with EDNS0 (which is enabled by default on BIND).

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