[nycbug-talk] dealing with drift

[Jim Brown]

* George Georgalis <george at galis.org> [2005-02-28 12:33]:
> On Mon, Feb 28, 2005 at 12:17:52PM -0500, Isaac Levy wrote:
> >Hi All,
> >
> >I was just wanting to post on some of the post-meeting conversations 
> >I've repeatedly over-heard about managing time-drift across clusters of 
> >machines- (you know who you people are...)
> >
> >How do folks like to do this?  Special tools beyond rockin' timed?  
> >Anyone know any good urls on the topic (either practical or acidemic)?
> 
> Am I missing something here? Isn't the obvious answer, for a cluster, to
> configure the headnode (whether is connected to internet and synced or
> not) to answer ntp queries from nodes, and configure the nodes ntp time
> server to use their headnode?  /usr/ports/net/ntp


I would add diversity here. Having only one time master is a SPoF.
Diverse routing is helpful as well.  

Just finished a similar exercise, though just for a collection
(not a cluster) of machines.

NTP on all BSDs but the OpenBSD box.  OpenNTP on that.

I do miss the ntpdc utility on OpenBSD.  Unless I'm missing something,
it's not easy to verify that you are, in fact, synched with another
NTP master.

Also- one other nit:   OpenNTP comes preconfigured to synch to
a pool of servers from ntp.org.  Why, I don't know.  Simplicity
maybe- but how am I supposed to verify *those* servers?

Best Regards,
Jim B.