[ntp:questions] Suitable ntp.conf for public NTP server?

Danny Mayer mayer at ntp.isc.org
Mon Oct 30 12:18:31 UTC 2006

Dennis Hilberg Jr wrote:
> "David Woolley" <david at djwhome.demon.co.uk> wrote in message 
> news:T1162112019 at djwhome.demon.co.uk...
> | In article <LZSdnVUGeNWTw9nYnZ2dnUVZ_s2dnZ2d at comcast.com>,
> | Dennis Hilberg Jr <dhilberg at comcast.net> wrote:
> |
> | > It works great.  So if/when my IP address changes, all I would have to 
> do is
> | > update the A record in my web's DNS configs.  Which I think would be 
> easier
> |
> | ntpd never re-resolves domain names, so any servers which change address
> | are lost until the next reboot.
> This would definitely pose a challenge if my IP changed.  So ntpd resolves 
> the domain once, then uses the resulting IP address until the next reboot or 
> service restart, correct?
> | Also, as a correctly operated system would not change IP addresses except
> | after extended downtime, it is generally assumed that these IP address
> | changes are the result of a deliberate policy to frustrate the operation
> | of servers.  It may just be that you are currently operating under
> | circumstances where that policy isn't working well.
> My server is on a network behind a router, and the router and modem never 
> get turned off.  Could this be why I keep the same IP for extended periods? 
> Comcast told me once that their lease period for the dynamic IP addresses is 
> one week, but almost always lease the same IP continuously.  I was going to 
> call Comcast last night and inquire about purchasing a static IP (if that's 
> even possible), but didn't get around to it.
> |
> | > server time-nw.nist.gov            iburst       # Microsoft Corporation,
> | > Redmond, WA
> |
> | I know this one is aliased as the Microsoft one, but is it really run by
> | Microsoft, or do they just pay NIST to be able to use it in Windows?
> | From what I've read, all the NIST servers are overloaded to the point
> | where they are not the best choice and this one may well be particularly
> | overloaded.
> All that I know about this server is what I gather from here: 
> http://ntp.isc.org/bin/view/Servers/TimeNwNistGov.  According to that link 
> the server is not running a Windows OS (surprising).   Maybe Microsoft 
> allowed the government to come in and set up a server using their network. 
> You may be right about it being overloaded, as under 'ntpq -p' it's always 
> flagged with the hyphen (-).  I was considering replacing it with a 
> different server.  I chose it only because of its proximity to me, and low 
> latency. 

Based on the information that you've given, I would strongly recommend
that it not be added to the pool. There are just too many issues. I
don't run the pool but I suspect that your configuration violates too
many of the guidelines that I would want to have in place for an NTP pool.


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