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Date:      Tue, 14 Jul 2015 09:43:30 -0400
From:      Paul Mather <paul@gromit.dlib.vt.edu>
To:        freebsd-stable <freebsd-stable@freebsd.org>
Subject:   Circular dependency between local_unbound and ntpd?
Message-ID:  <EDD17B95-0EA7-4C97-836D-7707416C0F07@gromit.dlib.vt.edu>

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I believe I ran afoul of a circular dependency between local_unbound and =
ntpd on my 10.2-PRERELEASE system.  I use a stock /etc/ntp.conf and use =
ntpd_sync_on_start=3D"YES".

Last night, a BIOS settings reset cause my CMOS clock to go WAY out of =
synch for the first time.  No problem, I thought: NTP will correct it at =
boot.

Wrong!

When my system booted, the time was not corrected.  Also, DNS resolution =
was not working.  I figured out it was because local_unbound relies on =
an accurately set clock, but the clock could not be set accurately =
because my stock ntp.conf requires working DNS resolution to reach the =
NTP servers.

That sounds like a potential circular dependency to me.

My workaround at the time was to look up 0.freebsd.pool.ntp.org on =
another system; stop ntpd; then do a ntpdate using the IP addresses to =
set the clock. Once the clock was set accurately, things were all hunky =
dory.

Does anyone have any suggestion for an automatic way around this?  I =
guess one way would be to put the IP address of an NTP server into my =
ntp.conf file, so at least one would be reachable without needing a =
working DNS?

My main concern is for those systems like my Raspberry Pi and Beaglebone =
Black that don't have a battery-backed clock.  I currently don't use =
local_unbound on those, but it seems like I'd encounter this problem =
routinely if I did.

Cheers,

Paul.=



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