On Sun, Feb 21, 2021, at 11:49 AM, Reco wrote: > On Sun, Feb 21, 2021 at 02:36:52PM -0500, Alan Corey wrote: > > That's why when you get a real time you adjust the times on your logged > > events. There's the time you got the time fix, everything else is N > > microseconds before that back to when you started recording. So you record > > back to <time fix time> minus <recording duration>. > > Yup. But by the time you get this "real time" you have other processes > (rpc.gssd, for instance) which already have managed to communicate with > someone (KDC), and are in the wrong state (krb5 time difference). > > RTC solves this, "fake RTC" (i.e. storing a timestamp on reboot) solves > it to some extent, but nothing else does. > > Reco
My goal is to replace my aging sheevaplug with something more modern. The sheevaplug exists for the purpose of providing network services (in particular, for the purposes of this discussion, NTP) to the 20 or so computers on my home LAN. To do that, it needs to have a reliable source of accurate time (to a few tens of milliseconds) as soon after boot as possible. The machine I'd like to use is a Raspberry Pi4B or a Pi0W. But without an RTC it won't do the job. Hence, I'm looking for an RTC module that can be easily added to a Pi4B or Pi0W with minimal (ideally none) soldering, and with Debian kernel support. If the module also does GPS, so much the better! But that's not strictly necessary. It would be very nice if it fits inside the existing case for the Pi4B. Do any of the devices that folks have mentioned here fit that bill? Thanks! Rick