Re: [Linuxptp-users] A10 SoC ptp4l - can't resync after losing GM

[Richard C. <ric...@gm...>]

On Thu, Feb 14, 2019 at 09:54:42AM -0600, John Lemonovich wrote:
> I have been running ptp4l on various intel FPGA Arria 10 SoC
> implementations, including one with the 10Gb MAC and a few with the HPS
> EMAC (stmmicro 1GbE) and it's all working very well.  One issue we're
> seeing is, if our A10 slave has been sync'd with a GM clock, and then that
> GM goes away (power cycled or even cable disconnected/reconnected) - our
> A10 ptp4l app won't resync to that same GM.  When the cable is
> reconnected, ptp4l does indeed select that same GM briefly as the BMC, but
> then it loses it upon announce receipt timeout expires and it never comes
> back.  I tried higher thresholds for annoucereceipttimeout, but it didn't
> help.

Use tcpdump to see whether Announce messages are missing.

Thanks,
Richard