Re: NTP Issues Today

[Sid Rao <srao () ctigroup com>]

Guys:

We were synchronized against multiple sources. Unfortunately the Navy NTP source contaminated multiple downstream 
sources. 

Unless you can trace all your sources, if these sources all have a root source you will break. 

Sid Rao | CTI Group | +1 (317) 262-4677

On Nov 21, 2012, at 8:01 AM, "Neil Harris" <neil () tonal clara co uk> wrote:

> On 21/11/12 12:34, Ryan Malayter wrote:
> > On Nov 19, 2012, at 6:12 PM, "Scott Weeks" <surfer () mauigateway com> wrote:
> >
> > > Lesson learned: Use more than one NTP source.
> > The lesson is: use MORE THAN TWO diverse NTP sources.
> >
> > A man with two watches has no idea what the time it actually is.
>
> Per David Mills, from the discussion linked upthread, this should be FOUR OR MORE...
>
> "Every critical server should have at least four sources, no two from the
> same organization and, as much as possible, reachable only via diverse,
> nonintersecting paths."
>
> Four, so that the remaining three can reach consensus even if one fails.
>
> -- Neil