[ntp:questions] ***SPAM*** Re: Bad NTP servers jeopardizing the pool.ntp.org initiative

Jan Ceuleers janspam.ceuleers at skynet.be
Mon Mar 26 18:42:03 UTC 2007


Wolfgang S. Rupprecht wrote:
> It has always bothered me that the TTL in the DNS record is stripped
> off by the resolver code.  There is already an indication in the DNS
> record how long the issuer of the record wants it to be used.  Careful
> DNS admins will even go so far as creeping the TTL down as a cut-over
> to a new IP address happens.  It would be ideal for a long-running
> program to just time out the IP address using this TTL and request a
> new one whenever the old one expires.

The potential problem with that is dynamic DNS, which uses artificially 
low TTL values. I'm convinced that many pool servers have dynamic DNS 
names (but I haven't verified this).

I would suggest that a better approach is (as others have proposed) not 
to re-resolve until there is a reachability problem.

Cheers, Jan

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