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Re: [Ntp] Antw: Re: Antw: [EXT] Local time in NTPv5?

Hal Murray <halmurray@sonic.net> Fri, 29 July 2022 16:27 UTC

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To: Miroslav Lichvar <mlichvar@redhat.com>
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From: Hal Murray <halmurray@sonic.net>
In-Reply-To: Message from Miroslav Lichvar <mlichvar@redhat.com> of "Fri, 29 Jul 2022 09:51:32 +0200." <YuORhPxzU1RIH5DL@localhost>
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Subject: Re: [Ntp] Antw: Re: Antw: [EXT] Local time in NTPv5?
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mlichvar@redhat.com said:
> You mean the TZ POSIX string (option 100) from RFC4833? That looks like it
> could work, even for announcing the DST change.

> So, I guess the question is now are there any use cases for the local time in
> NTP without DHCP?

That only works if the DHCP servers in use actually support it.

Is there a tool for poking at DHCP servers to see what they provide?  I poked 
around a bit but diddn't find one.

I scanned the man page for the ISC DHCP server and didn't find any mention of 
NTP or time zones.  (ntp was mentioned as a logging option.)

If a client gets its IP Address from a server, does it latch on to that server 
and ignore others?  Or will it try broadcasting to find other servers before 
giving up?  Can we setup a DHCP server that only provides time zone info?



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