r2 - 2004-12-18 - 05:08:00 - HarlanStennYou are here: NTP >  Support Web > ConfiguringNTP > ConfiguringRefclocks > UndisciplinedLocalClock
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ntp-4.2.8p14 was released on 03 March 2020. It addresses 2 medium-severity security issues in ntpd, and provides 47 non-security bugfixes and 4 other improvements over 4.2.8p13.

Please see the NTP Security Notice for vulnerability and mitigation details.

Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
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" graphics="on"}% REFACTOR See UndisciplinedLocalClockDev for discussion of this topic.

A Local Refclock should be configured on a machine if you want that machine to serve time to other machines even if there is no "proper" refclock available.

If a machine is "visible" on the internet and is using a local refclock, the stratum of the local refclock should not be lower than, say, 8, as it would be Bad to have machines outside your network believing your unsychronized local clock.

Otherwise, you can find the "best" machine in your set of servers and configure its local refclock at no better than 2 stratum levels below the worst stratum where the machine would ordinarily run. You can find your second best machine in your set of servers and configure its local refclock at 2 stratum levels worse than that.

For example, if ServerA is the "best" and ServerB is the second best server in your local time server pool, and these servers do not serve time to machines outside your network, and they ordinarily synchronize with machines that, at worst case, are at stratum 3, then you should configure ServerA's local refclock at stratum 5 and ServerB's local refclock at stratum 7.


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