I'm using the i210 with phc2sys on my Supermicro and the jitter as reported
by NTP is 954 nanoseconds, i.e., just sub-microsecond. I have gotten
similar results with the Supermicro's system board 82547L NICs (my paper at
the ION PTTI Boston, Dec. 2014, Developing Low Cost NTP Stratum 1 Servers
with Linux PTP an GPS), and have tested an 82547L on the HP ProLiant
DL120G6 with the FEI-Zyfer Gsync at USNO, and again similar performance. I
can say with confidence that all three, the i350, i210, and 82547L work
well with linuxptp. And with NTP v. 4.2.8p1.
Rich
On Thu, Feb 26, 2015 at 4:43 PM, Gary E. Miller <g...@rellim.com> wrote:
> Yo Rich!
>
> On Thu, 26 Feb 2015 16:29:00 -0500
> Rich Schmidt <schmidt.r...@gmail.com> wrote:
>
> > The config file for ptp4l was just as provided in my last note. There
> > wasn't much else to setup.
>
> Uh, sorry, already deleted...
>
> > I disabled chrony, as I am serving NTP.
>
> Uh, say what? Chronyd is used to serve NTP, I hope you are not using ntpd
> instead? I find chrony much superior in timeserving to chronyd.
>
> > I have an FEI-Zyfer Gsync II
> > Time and Frequency Processor acting as PTP Grandmaster. I configured
> > the IP address of an i350 NIC to the same subnet as my Grandmaster.
> > Using "ethtool -T" I find that my PHC is number 0, which is /dev/ptp0.
>
> Could I please get the ethtool -T dump? I'm trying to figure out
> what features do what...
>
> > So my ptp4l command is:
> > nohup nice --20 /usr/local/sbin/ptp4l -m -f /etc/ptp4l.conf -i eth2 -p
> > /dev/ptp0 > /var/log/ptp4l.log &
> > and to steer my system to the PHC I run:
> > nohup nice --20 /usr/local/sbin/phc2sys -q -m -c CLOCK_REALTIME -s
> > /dev/ptp0 -E linreg -O 0 -l 7 >/var/log/ptp/phc2sys.log &
> >
> > Note that my Grandmaster is on UTC , not PTP timescale, so I specify
> > -O 0 for the UTC offset for phc2sys.
> > Then I run as an NTP stratum 1 server using the local clock refclock
> > in /etc/ntp.conf:
> > server 127.127.1.0 prefer
> > server 192.5.41.40 noselect
> > fudge 127.127.1.0 stratum 0
> > fudge 127.127.1.0 refid PTP
>
> Hmm, no secondary sources? How do you know you do not have the large
> offset I see?
>
> > Not everyone has an FEI-Zyfer Gsync for a grandmaster. At home I have
> > two Supermicro Atom servers, one is grandmaster, one is slave. The
> > grandmaster has a GPS receiver outputting 1PPS which is connected to
> > the DCD pin on the internal COM2 serial header. Here the NTP
> > refclock_nmea driver synchronizes the system clock of the
> > grandmaster. Then 'phc2sys -s CLOCK_REALTIME -c /dev/ptp0" steers the
> > PHC to system time, while ptp4l provides PTP on an Intel i210 NIC.
>
> And who is sending SHM 0? And how?
>
> > On the slave Supermicro server a second Intel i210 NIC synchronizes
> > to the grandmaster as above. For complete details google "Developing
> > Low-Cost NTP Stratum 1 Servers with Linux PTP and GPS".
>
> This one?
>
>
> http://www.academia.edu/10312557/DEVELOPING_LOW-COST_NTP_STRATUM_1_SERVERS_WITH_LINUX_PTP_AND_GPS
>
> Sadly, after jumping through several hoops, it would not let me get
> to the paper (eventual 404). Got a better URL?
>
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701
> g...@rellim.com Tel:+1(541)382-8588
>
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