default $ttl

[Joseph S D Yao]

On Wed, May 30, 2001 at 02:26:26PM -0400, Fabiola Caceres wrote:
> 
> Hi
> is there any difference in doing:
> 
> $TTL    86400
> @       IN      SOA ns1.infi.net. hostmaster.infi.net.
> rest of zone file goes here...
> 
> ------------------
> OR
> 
> @ 86400 IN      SOA ns1.infi.net. hostmaster.infi.net.
> (
>         2001051602      ; Serial
>         10800           ; Refresh after 3 hours
>         3600            ; Retry after 1 hour
>         604800          ; Expire after 1 week
>         86400           ; Minimum TTL of 1 day
> )
>         IN      NS      ns1.infi.net.
>         IN      NS      ns2.infi.net.
>         IN      NS      ns3.infi.net.
>         IN      NS      ns4.infi.net.
>         IN      A       216.33.107.214
> www     IN      CNAME   vh50003.vh5.infi.net.
> web     IN      CNAME   vh50003.vh5.infi.net.

Absolutely.

The first (a) is legal, and (b) establishes a default TTL for all
records that follow.

The second is not legal, because no default TTL has been established,
and all records after the SOA have no established TTL.  BIND 8.2ff will
give a warning, and use the negative TTL [labeled as "minimum", above]
as the value for the default positive TTL.  BIND 9 will object and not
accept it.

Capish?

-- 
Joe Yao				jsdy at cospo.osis.gov - Joseph S. D. Yao
OSIS Center Computer Support					EMT-B
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