[ntp:questions] server and peer lines correct?

Harlan Stenn stenn at ntp.org
Sat Apr 5 23:58:13 UTC 2014

"Jason Rabel" writes:
> I'm reconfiguring my NTP setup to try and be somewhat fault-resistant
> if GPS blacks out since my receiver is in the window and only picks up
> facing east.
> I have four stratum-1 servers connected to GPS receivers. The
> stratum-1 servers are configured to be completely independent, they
> don't talk to each other (for reasons beyond the scope of this
> post). They get their time solely from their GPS module.
> I have three stratum-2 servers which I'm trying to make my primary
> sources for time for all the clients on the network. As mentioned
> before sometimes I loose GPS reception, and sometimes I will take one
> of the S1 servers down so I can tinker with the internals.
> The three configs for my S2 servers are as follows. I'm including just
> the bare necessities, the restrict lines are all correct and other
> various options. S1 = Stratum 1, NTPx = Stratum 2 servers.
> All three servers have:
> server S1-1 iburst
> server S1-2 iburst
> server S1-3 iburst
> server S1-4 iburst


> Then they differ as follows:
> NTP1:
> peer NTP2 iburst
> peer NTP3 iburst
> NTP2:
> peer NTP1 iburst
> peer NTP3 iburst
> NTP3:
> peer NTP1 iburst
> peer NTP2 iburst

Perfectly fine, especially since you are concerned about the case where
all of the S1 servers may be gone.
> Is there a command to check that they are setup properly in a peering
> configuration?

Manually, I like 'ntpq -p NTP1'.  Since all of your S2 servers peer with
one another this will usually be enough.  If you want to check more, you
can easily check the others.

> If all my S1 servers go offline, will the S2 servers still function
> since their only valid time source would be each other? Or would I
> need to add some additional settings (like orphan)?

When all the S1 servers go down the S2 servers will "ratchet down" until
they are all unsynch'd.

For what you describe I'd recommend you use orphan mode.


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