[Pool] Off by a second leap second failures

Miroslav Lichvar mlichvar at redhat.com
Wed Jul 15 16:44:55 UTC 2015

On Wed, Jul 15, 2015 at 09:31:23AM -0700, Ask Bjørn Hansen wrote:
> What is the earliest before a scheduled leap second that you can set the flag? I know what ntpd does (or is supposed to), but I thought that strictly speaking you are allowed to set it at the beginning of the leap second month?

The NTPv4 RFC is ambiguous on this point, there is "last minute of the
day has 61 seconds" and also "last minute of the current month". I
think it's meant to be only the last day, i.e. what the current
versions of ntpd do. Allowing the leap to be announced in whole month,
as we can see with ntp versions before 4.2.6, was a bad idea.

Miroslav Lichvar

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