[ntp:questions] orphan mode and layered redundancy

Florin Andrei florin at andrei.myip.org
Fri May 27 00:28:46 UTC 2011

On 05/26/2011 04:40 PM, Dave Hart wrote:
> On Thu, May 26, 2011 at 22:04 UTC, Florin Andrei<florin at andrei.myip.org>  wrote:
>> It is unclear to me whether "tos orphan N" needs to have different values
>> between NTP servers and cluster members. I assumed it needs to be higher for
>> cluster members.
> Only cluster members need orphan mode (for when the upstream server(s)
> are unreachable).  They must all use the same orphan stratum for
> orphan mode to work between them -- ntpd recognizes a source as
> operating as a potential orphan parent by its stratum.

But could I use orphan mode on the local NTP servers, with a lower 
stratum? The clusters are not the only NTP clients, and I'd like the 
local NTP servers to keep some semblance of consistency in case the 
Internet goes offline.

Would it break anything if I do "tos orphan 10" on the local NTP 
servers, and "tos orphan 12" on the cluster nodes?

>> Do I have to add "tos cohort 1" anywhere? Or would the "peer" commands take
>> care of everything?
> Orphan mode will become effective only when all non-orphan sources are
> not selectable.  In that case, you don't need "tos cohort 1" to allow
> you to consider peers at the same stratum as potential sources -- you
> won't be operating at the same stratum once the upstream sources are
> not selectable.

Got it, I'll remove cohort.

Florin Andrei

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