TTL on glue records and PTR records

Len Conrad LConrad at Go2France.com
Sat Aug 25 17:58:33 UTC 2001



>I'm a parent zone, gwu.edu, and I've been having a discussion with one of the
>admins of my delegated subdomains, va.gwu.edu, regarding a couple of issues:
>1. I thought that my zone TTL only affected the glue records of the delegated
>subdomain, NOT the entire zone.

TTL´s are valid only for the zone they occur in.

>  Doesn't the SOA information in the zone file
>of the delegated subdomain set the TTL for all records in the subdomain?

no.  And recently the SOA TTL is no longer the zone default TTL nor the 
negative-TTL but just the SOA´s TTL.

>2. He has multiple "A" record names pointing to the same IP addresses for his
>nameservers

As "documentation" records, those NS records in his zone file won´t be 
queried by DNS´s following referrals.  So the delegation NS records (in 
your DNS as parent) will provide the effective TTL´s.

Len


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