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Re: Length of txt records

2004-06-21 10:54:05
On Mon, 21 Jun 2004 12:39:42 -0400, Erik Aronesty 
<info(_at_)zoneedit(_dot_)com> wrote:
Some companies have lots of remote offices which users can send mail from.
We have plenty of domains that have more IP's than can fit in a 255-char TXT
record.

I believe a DNS TXT record can be up to 65535 (0xFFFF) bytes long as
it's length is defined by 16 bit unsigned number
(http://rfc.net/rfc1035.html#s3.2.1. - RDLENGTH field).

I understand some DNS servers may enforce lower limits, but a TXT
record can be over 255 (of course, keeping the packet under the usual
UDP single packet size of about 1500 bytes is a good idea).

--
Tim


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