Need trusted NTP Sources

Jay Ashworth jra at
Sun Feb 9 00:48:49 UTC 2014

---- Original Message -----
> From: "Matthew Huff" <mhuff at>

> Working in the financial world, the best practices is to have 4 ntp
> servers (if not using PTP).
> 1) You need 3 to determine the correct time (and detect bad tickers)
> 2) If you lose 1 of the 3 above, then you no longer can determine the
> correct time
> 3) Therefore with 4, you have redundancy.
> We have two Symmetricom Stratum 1 time servers synced via GPS with
> Rubidium oscillators, and two RHEL 6 servers running ntpd for our 4
> servers.

As I've noted, I had *nine* external peers; 3 shared by both machines
(commercial and NIST strat-1's), and 3 each from us.pool, which were
generally different servers; I did keep an eye on that.

And the NTP servers were monitored.

I'm stupid, but I'm not crazy. :-)

-- jra

Jay R. Ashworth                  Baylink                       jra at
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates          2000 Land Rover DII
St Petersburg FL USA      BCP38: Ask For It By Name!           +1 727 647 1274

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