BIND 9 and TTLs

[Jim Reid]

>>>>> ">" == The infamous \"Brian\" <The> writes:

    >> Why now require yet another TTL directive when one exists in
    >> the SOA?

Read RFC2308. The TTL value in the SOA record is now used to control
negative caching (how long a server remembers that some name does not
exist). That means each RR in the zone file needs an explicit TTL. The
easiest way to do that is with a $TTL directive at the top of the zone
file. BIND has implemented this for a long time. It predates
BIND9. 8.2 supported RFC2308. And questions about the "no default TTL
set, using SOA" message in the BIND8 logs are asked here almost
weekly.