[ntp:questions] NTP, no external time source, peering "Undisciplined Local Clocks" ?

Marco Molteni mmolteni at cisco.com
Tue Oct 18 14:19:11 UTC 2005

Say I have a network with no access to the internet, and I have no
external time reference (no GPS or atomic or whatever clock available).
I am using the NTP reference implementation ntpd on FreeBSD.

The network is composed of 3 hosts: A, B and C.

I know I can tell NTP to use the local clock as a time reference, what
is called an "Undisciplined Local Clock" in the NTP documentation.

Say I don't know if a clock is better than the other, so by configuring
B and C to use A as server I risk to have a not so good time if A is 

Can I configure A,B,C to peer with each other in a meshed fashion, so
to have each clock influenced by all the others? From what I read I 
should use the following configuration file on each host:

========== /etc/ntp.conf ======
peer hostA
peer hostB
peer hostC

would it work? Is it the best way to obtain the "best" time assuming
I don't know if a clock is better than another?


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