On 2026-02-27 10:47 +11, marka <[email protected]> wrote:
>> On 27 Feb 2026, at 06:41, Florian Obser <[email protected]> wrote:
>> 
>> On 2026-02-26 15:50 UTC, Jim Reid <[email protected]> wrote:
>>>> On 26 Feb 2026, at 15:11, Florian Obser <[email protected]> wrote:
>>>> 
>>>> How can the LocalRoot server figure out what the real expire time is
>>>> when using http? At what time should it stop using the zone file and
>>>> switch to querying the root name servers?
>>> 
>>> Surely the SOA record's metadata answers those questions? Maybe I'm
>>> missing something.
>> 
>> Yes, it's the expire time. The root zone currently expires 604800
>> seconds (i.e. one week) after it gets loaded:
>> 
>> . 86400 IN SOA a.root-servers.net. nstld.verisign-grs.com. (
>> 2026022602 ; serial
>> 1800       ; refresh (30 minutes)
>> 900        ; retry (15 minutes)
>> 604800     ; expire (1 week)
>> 86400      ; minimum (1 day)
>> )
>> 
>> Note that this is an interval, not a time stamp. If I load a root zone
>> from ten days ago it will be valid for another week. Surely that is not
>> correct.
>
> That’s why nameservers look at file modification times when setting the
> expiry time.  It’s also why they back date file modification times when
> using EDNS EXPIRE so that the zone will expire at the correct time after
> a restart.

Sure, but Jim's assumption was that the absolute expire time can be
worked out from the SOA record alone, which is not true.
We have this solved with (A|I)XFR + EDNS EXPIRE, but the draft needs
words on how to handle the expire time when fetching a txt file from a
webserver.

-- 
In my defence, I have been left unsupervised.

_______________________________________________
DNSOP mailing list -- [email protected]
To unsubscribe send an email to [email protected]

Reply via email to