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Re: ntpdate(8) and unbound(8) dependencies during boot

Sad Clouds <> writes:

> On Sun, 11 Oct 2020 12:49:16 +0200 (CEST)
> Havard Eidnes <> wrote:
>> > The question is whether we ought to do something to break this
>> > circular dependency in our default install by specifying one or two
>> > (depending on "minsane" and resiliency conciderations) ntp servers
>> > via IP address?  The issue then becomes "which IP address(es)" and
>> > "how can that scale"?
>> ...or improve the documentation for potentially RTC-less systems
>> about the rc.conf ntpdate_hosts workaround.
>> Regards,
>> - Håvard
> If you look at /etc/rc.d/ntpdate script, it checks if "ntpdate_hosts"
> is empty and if yes, attempts to extract hosts from /etc/ntp.conf
> I would suggest adding the following logic:
> 1. Extract hosts and check if they are hostnames and not IP addresses.
> 2. Attempt to resolve each one of them. If they all fail, fall back to
> hardcoded list of IP addresses that point to public NTP servers.
> The hardcoded NTP servers list would need to be something that is not
> likely to have their IP addresses changed and are always available,
> similar to CloudFlare or Google public DNS servers. This is not 100%
> full proof, but should work for any machine that is able to route
> NTP packets to the Internet.
> The man page for ntpdate talks about NetInfo support. No idea what this
> is (maybe somehow similar to SRV records?), but if this is enabled, NTP
> server name/IP can be omitted and ntpdate somehow finds suitable one
> automagically. This probably still needs fully working DNS service.

I would rather not add this magic code, and also not configure addresses
like these.  To me this is a special case of running NetBSD on an
RTC-less machine, which I see as a bit irregular.   It's really a
problem for deployed machines without console access.

It would be fair to point this out in the raspberry pi howto, though.

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