chaotic serial numbers

[Jim Reid]

    >> I read somewhere that you could synchronise other slave server
    >> by making the serial number on the authoritative master name
    >> server zero and then incrementing the number after the TTL
    >> expires.  Is that it?

No. Old versions of BIND allowed this. But the feature violated the
semantics of serial number arithmetic defined in RFC1982 and
therefore had to be dropped. I quote from that RFC:

   Caution should also be exercised before causing the serial number to
   be set to the value zero.  While this value is not in any way special
   in serial number arithmetic, or to the DNS SOA serial number, many
   DNS implementations have incorrectly treated zero as a special case,
   with special properties, and unusual behaviour may be expected if
   zero is used as a DNS SOA serial number.