05.05.2012 19:42, Colin Guthrie kirjoitti: > 'Twas brillig, and David Walser at 05/05/12 17:15 did gyre and gimble: >> Colin Guthrie wrote: >>> This is why the kernel will automatically does the sync for you every 12 >>> minutes when an ntp daemon is running. This is the recommended method. >> >> How does the kernel know when an ntp daemon is running in user space? Does >> it work with chrony, or only ntpd? > > I don't know the internals. It works with either chrony or ntpd. > >>> So unless we have a proper frame of reference, (user set time, ntp >>> protocol time) then there should be no manual sync. >> >> Does the kernel then sync the hwclock when you change the time manually, >> including with rdate or ntpdate? > > It won't do it automatically when doing that. It's really up to whatever > tool changes the date/time to do that as needed I think.
And how could such a tool know if RTC should be set to UTC or local time? .. or are we expected to patch them to parse /etc/sysconfig/clock for that? Well, I guess the tool could detect that by looking at the RTC/sysclock offset as well, though seems a bit hacky... What is the expected "right way" to do it, if systemd policy is to not sync on shutdown? -- Anssi Hannula
