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

Danny Mayer mayer at ntp.isc.org
Sat Mar 31 01:34:17 UTC 2007


Jan Ceuleers wrote:
> Wolfgang S. Rupprecht wrote:
> 
> (I suggested that pool members with non-static IP addresses could be 
> accommodated by the pool).
> 

Well you shouldn't have. It just won't work for any useful time period.

>>> And the protocol already exists: it's called dynamic DNS.
>> Care to flesh out how you envision this working?
> 
> The pool is essentially a fancy name server. Pool members could use the 
> existing dynamic DNS protocol to register their current IP address with 
> the pool. Perhaps in addition to registering with their regular dynamic 
> DNS provider, if they provide services other than NTP.
> 
> Advantages: dynamic DNS clients exist for lots of platforms.

Clients yes, servers no. The pool is a bunch of *servers* not clients so
why are you talking about the clients?

> Disadvantages: I don't know whether dynamic DNS servers are readily 
> available to be integrated with the rest of the pool server software. 
> Moreover, the pool would also need to use low TTL values (but then I 
> think it already is).
> 

The only question would be if there are any *non*-dynamic DNS servers
readily available but why ask the wrong question.

> The other disadvantage is that pool clients might, for a limited period 
> of time, hammer whoever next receives the IP address previously held by 
> a pool server. Malevolant such inherintants of IP addresses might reduce 
> the perceived quality of the pool by telling the wrong time.
> 

No, this isn't a limited length of time it's a long time, possibly
months until it ceases and even then maybe not. You should not be
guessing at the longevity of the provided IP address providing NTP service.

Danny



More information about the questions mailing list