Hi all, Now I managed to solve the 2018 issue by just using the default conf installed with linuxptp for the master.
I have 3 different Master slave setups where the slaves are sending messages between another which include the timestamp from the Transmission time to calculate the latency in the reception. Now the problem I am facing is that for two of the setups, I see coherent latency values but for the other one, I see some negative latency values, which implies that that Master slave setup has a different and wrong clock than the two others. All 3 setups are identical and are taking the source from a GPS signal. The only thing that is different is that in this setup, the computer with GPS device is switched on from longer time. I can remotely reboot it but not switch off from electricity and switch on again. Is it possible that this is the issue and it is syncing to a not uptaded clock? With the two that I can manually connect to electricity values are quite good. Thanks a lot in advance for the answers. Best regards, Federico Murciano M.Sc. Elektrotechnik - Telecommunications Engineer federico.murci...@dai-labor.de Tel. +49 (0) 30/314 -74 025 / Mob. +49 157 8642 4850 Future Communication Networks DAI-Labor Technische Universität Berlin Fakultät IV – Elektrotechnik & Informatik Sekretariat TEL 14 Ernst-Reuter-Platz 7 10587 Berlin, Germany http://www.dai-labor.de/ DAI-Labor - Distributed Artificial Intelligence Laboratory Chief Executive Director: Prof. Dr. Dr. h.c. Sahin Albayrak ________________________________________ Von: Vladimir Oltean <olte...@gmail.com> Gesendet: Donnerstag, 24. März 2022 19:09 An: ch...@chriscaudle.org Cc: linuxptp-users@lists.sourceforge.net Betreff: Re: [Linuxptp-users] phc2sys not synchr. to right time and date On Thu, Mar 24, 2022 at 09:14:08AM -0500, Chris Caudle wrote: > On Thu, March 24, 2022 5:02 am, > linuxptp-users-requ...@lists.sourceforge.net wrote: > > From: Federico Murciano <federico.murci...@dai-labor.de> > > Subject: Re: [Linuxptp-users] phc2sys not synchr. to right time and > > date > > Message-ID: <1648115598945.22...@dai-labor.de> > > > Thank you for your answer. Yes this is in the slave computer. In the > > master computer I only execute the following, which is working for my > > other setup (with replicated master and slave devices): > > > > cat ptp.cfg > > [global] > > tx_timestamp_timeout 10 > > step_threshold 1 > > > > sudo ptp4l -A -i eth0 -m -f ptp.cfg > > Then what process is expected to set the time for the PHC? That seems to > be a missing step in your configuration. Perhaps the better question is > why does the other setup ever work? > > -- > Chris Caudle (there might be other reasons why his setup is working, but) Some kernel Ethernet drivers have a bad habit of writing the current (UTC) system time (derived from the battery-backed RTC) into the PHC current (TAI) time at boot. You're off by 37 seconds, but hey, at least it's 2022, so the time _must_ be right! https://elixir.bootlin.com/linux/latest/source/drivers/ptp/ptp_qoriq.c#L504 _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
