On Wed, Jun 28, 2023 at 06:37:42PM -0300, Elder Costa wrote: > I ran a test with the system below. GM and AM running SW timestamp. > The System clocks of the SOM and the AM synchronize with the GM's but > there is an offset of 37s (GM's 37s ahead the other two). I tried > using --utc_offset on the ptp4l instance running in the GM with no > success: no matter the value, the offset stays in 37s. What am I doing > wrong?
On the GM, when you run ptp4l with SW time stamping, then it will serve UTC and so ptpTimescale will be 0 (false). IOW, your setup cannot use TAI at all. You need to configure phc2sys on host "SOM" with an UTC/TAI offset of zero using this option: -O [offset] sink-source time offset in seconds (0) So something like: phc2sys -m -q -O0 -S 0.001 -s eth_head phc2sys -m -q -O0 -S 0.001 -c eth_am -s CLOCK_REALTIME HTH, Richard > System clock GM +--> System clock SOM --+ System clock AM > | | | ^ > | | | | > | | v | > | phc2sys phc2sys | > | | | | > | | | | > v | v | > ptp4l(M/SW) ptp4l(S/HW) ptp4l(M/HW) ptp4l (S/SW) > | | | | > | | | | > v | v | > enp3s0 <----> eth_head eth_am <-----> eth0 (SW ts) > > > _______________________________________________ > 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
