Maximum # of secondaries?

[Barry Margolin]

   Date: Wed, 06 Oct 1999 17:52:37 -0400
   From: Kevin Darcy <kcd at daimlerchrysler.com>

   If too many NS records exist for a zone, though, one could experience problems
   with UDP-packet-size limitations. But that would generally only affect servers,
   since clients don't usually make NS queries. And it's not a fatal error in any
   case, just a little inefficient.

True.  Although if most of the servers are in the same domain, DNS packet
compression will usually solve the packet size problem.  This is why all
the root servers were renamed to <something>.ROOT-SERVERS.NET -- that
common suffix only has to appear once in these packets.  There are 13 root
servers and the response to "dig . ns" is only 436 bytes.  There are 12
.COM servers in two 2LD's (some in ROOT-SERVERS.NET, some in
GTLD-SERVERS.NET) and this response is only 434 bytes.

-- 
Barry Margolin, barmar at bbnplanet.com
GTE Internetworking, Powered by BBN, Burlington, MA