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Building a Stratum 1 NTP Server Using Odroid C2

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  • J
    jcpingu @bingo600
    last edited by Jun 21, 2021, 9:06 PM

    @bingo600
    I have a newer revision of the GPS Board. Its default baud is 115200

    1 Reply Last reply Reply Quote 0
    • J
      jcpingu @bingo600
      last edited by Jun 21, 2021, 9:11 PM

      @bingo600
      I will check $GNRMC. It looks like I am not getting them...

      1 Reply Last reply Reply Quote 0
      • J
        jcpingu @bingo600
        last edited by Jun 21, 2021, 9:23 PM

        @bingo600
        Here you go:
        95285b07-d93b-4144-a19c-448d783c8259-image.png

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        • S
          stephenw10 Netgate Administrator
          last edited by stephenw10 Jun 21, 2021, 9:57 PM Jun 21, 2021, 9:51 PM

          Does ppstest work against gpspps0? If not did you create the symlink?

          What does your ntp.conf file look like? Did you change the mode for 115200 baud?

          Edit: Yeah you probably want mode 81 there.

          Steve

          J 2 Replies Last reply Jun 21, 2021, 10:15 PM Reply Quote 0
          • J
            jcpingu @stephenw10
            last edited by Jun 21, 2021, 10:15 PM

            @stephenw10
            Yes per the guide Symlink is used, there's a file that use the below:
            KERNEL=="ttyS1", SYMLINK+="gps0"
            KERNEL=="pps0", SYMLINK+="gpspps0"

            Also, how do I edit ntp.conf? When I enter it, I get permission denied
            79f235ba-6626-432e-acc8-b2f19fe3c546-image.png

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            • J
              jcpingu @stephenw10
              last edited by jcpingu Jun 21, 2021, 10:23 PM Jun 21, 2021, 10:22 PM

              @stephenw10
              Here is the ntp.conf content in the guide. Are you saying to change mode 17 to 81?

              server 127.127.20.0 mode 17 minpoll 4 maxpoll 4 prefer
              fudge 127.127.20.0 flag1 1 refid GPS

              security

              restrict default kod limited nomodify nopeer
              restrict -6 default kod limited nomodify nopeer

              Local users may interrogate the NTP server fully.

              restrict 127.0.0.1
              restrict -6 ::1

              stats

              driftfile /var/lib/ntp/ntp.drift

              Enable statistics logging.

              statsdir /var/log/ntpstats/
              statistics loopstats peerstats clockstats
              filegen loopstats file loopstats type day enable
              filegen peerstats file peerstats type day enable
              filegen clockstats file clockstats type day enable

              leap file

              leapfile /var/lib/ntp/leap-seconds.list

              1 Reply Last reply Reply Quote 0
              • S
                stephenw10 Netgate Administrator
                last edited by Jun 21, 2021, 11:22 PM

                Yes because, like it says there, mode 17 is for 9600 baud and your GPS is running at 115200. So currently it's seeing no data.

                J 3 Replies Last reply Jun 22, 2021, 1:48 AM Reply Quote 1
                • J
                  jcpingu @stephenw10
                  last edited by Jun 22, 2021, 1:48 AM

                  @stephenw10
                  Thank you. I will advise latest status...

                  1 Reply Last reply Reply Quote 0
                  • J
                    jcpingu @stephenw10
                    last edited by Jun 22, 2021, 2:09 AM

                    @stephenw10
                    The good News:
                    b022b744-34df-44b1-b57b-6840e82c4dca-image.png

                    The not so good news, I am still seeing clock unsynchronized:
                    6f2be03c-eca7-445a-811f-dfa31af4a896-image.png

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                    • J
                      jcpingu @stephenw10
                      last edited by Jun 22, 2021, 2:55 AM

                      @stephenw10
                      I was looking @ your example, and I see that it also shows this error:
                      Jun 21 18:35:03 ntpd 56634 kernel reports TIME_ERROR: 0x41: Clock Unsynchronized

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                      • S
                        stephenw10 Netgate Administrator
                        last edited by Jun 22, 2021, 10:49 AM

                        Yes, I expect it to show that when ntpd is first started. It won't sync until sometime later when ntp is confident the time data it has is correct.
                        Wait some time and recheck. Or it may have already sync'd there since it show an offset or effectively 0 (2Ξs) from the GPS time.

                        Steve

                        J 2 Replies Last reply Jun 22, 2021, 3:57 PM Reply Quote 1
                        • J
                          jcpingu @stephenw10
                          last edited by Jun 22, 2021, 3:57 PM

                          @stephenw10
                          Thank you for all your help. I truly appreciate your patience and kindness. I still see the error this morning. However ntpq -p is showing the right output. I am assuming there's nothing I can do about the error...
                          f64cc788-75d7-4e80-b6de-1709d5f94363-image.png

                          B 2 Replies Last reply Jun 22, 2021, 4:46 PM Reply Quote 0
                          • B
                            bingo600 @jcpingu
                            last edited by Jun 22, 2021, 4:46 PM

                            @jcpingu

                            Have a look here
                            https://serverfault.com/questions/1048870/ntpd-fails-to-sync-time-error-0x41-clock-unsynchronized

                            Especially this command : ntpq -c sysinfo

                            Normally as @stephenw10 mentioned , ntpd won't just accept a new clocksource , before investigating if it's "ok".

                            I usually expect approx 5 minutes (after daemon start) for the daemon to "trust/select" a clocksource.

                            If you find my answer useful - Please give the post a 👍 - "thumbs up"

                            pfSense+ 23.05.1 (ZFS)

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                            J 1 Reply Last reply Jun 22, 2021, 4:53 PM Reply Quote 1
                            • J
                              jcpingu @bingo600
                              last edited by Jun 22, 2021, 4:53 PM

                              @bingo600
                              Here's the output of that command. I will check out the link. Thanks...
                              ff838b1f-9a99-4f6b-a70c-f2fe599803ff-image.png

                              1 Reply Last reply Reply Quote 0
                              • J
                                jcpingu @stephenw10
                                last edited by Jun 22, 2021, 5:11 PM

                                @stephenw10
                                This is my ntp.conf file. Based on bingo600 comments above. Is there anything else that needs to happen here?

                                server 127.127.20.0 mode 81 minpoll 4 maxpoll 4 prefer
                                fudge 127.127.20.0 flag1 1 refid GPS

                                security

                                restrict default kod limited nomodify nopeer
                                restrict -6 default kod limited nomodify nopeer

                                Local users may interrogate the NTP server fully.

                                restrict 127.0.0.1
                                restrict -6 ::1

                                stats

                                driftfile /var/lib/ntp/ntp.drift

                                Enable statistics logging.

                                statsdir /var/log/ntpstats/
                                statistics loopstats peerstats clockstats
                                filegen loopstats file loopstats type day enable
                                filegen peerstats file peerstats type day enable
                                filegen clockstats file clockstats type day enable

                                leap file

                                leapfile /var/lib/ntp/leap-seconds.list

                                1 Reply Last reply Reply Quote 0
                                • S
                                  stephenw10 Netgate Administrator
                                  last edited by Jun 22, 2021, 5:28 PM

                                  No, I think it's working as expected.
                                  That error will always appear when you restart ntpd for any reason. I would only vbe concerned if it is still logging new errors after running for some time.

                                  Steve

                                  1 Reply Last reply Reply Quote 1
                                  • B
                                    bingo600 @jcpingu
                                    last edited by bingo600 Jun 22, 2021, 7:05 PM Jun 22, 2021, 6:02 PM

                                    @jcpingu

                                    Try to put in a few ntp pool servers for reference.

                                    Add this to your ntp.conf

                                    # Internet time servers for sanity
                                    server 0.pool.ntp.org iburst prefer 
                                    server 1.pool.ntp.org iburst 
                                    server 2.pool.ntp.org iburst 
                                    server 3.pool.ntp.org iburst
                                    

                                    From here:
                                    http://doc.ntp.org/4.2.6/drivers/driver20.html

                                    It seems like the $GNRMC is not a supported sentence , and that either
                                    $GPZDA or $GPZDG must be sent for the NTP system to be fully autonomous. As in being able to set date/time fully via NTP.

                                    What GPS model do you have ?
                                    Is it from "China" ... Where most Ublox'es are "fakes"

                                    This is not an "all bad" mesage , as the PPS still will keep your clock extremely accurate (sub seconds) . You just need a bit of help setting the seconds.

                                    But it's strange that the nmea driver is so picky.
                                    Maybe gpsd would help here

                                    /Bingo

                                    If you find my answer useful - Please give the post a 👍 - "thumbs up"

                                    pfSense+ 23.05.1 (ZFS)

                                    QOTOM-Q355G4 Quad Lan.
                                    CPU  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                    LAN  : 4 x Intel 211, Disk  : 240G SAMSUNG MZ7L3240HCHQ SSD

                                    B J 2 Replies Last reply Jun 22, 2021, 6:43 PM Reply Quote 0
                                    • B
                                      bingo600 @bingo600
                                      last edited by bingo600 Jun 22, 2021, 7:03 PM Jun 22, 2021, 6:43 PM

                                      @bingo600

                                      The NTP nmea refdriver doc is "buggy"

                                      I just had a quick glance at the source
                                      https://github.com/ntp-project/ntp/blob/master-no-authorname/ntpd/refclock_nmea.c

                                      08de05e8-b0c3-4db4-9d95-939ec3e666a3-image.png

                                      And it's comparing the last 3 (4) characters in the sentence so any RMC works

                                      And it seems like it's parsing/setting the date from RMC sentenses too.
                                      The only thing ZDA is providing "extra" is YYYY vs YY from RMC.

                                      c398f0a9-851a-409d-903c-f38f9d323831-image.png

                                      It should be possible to make a working NTP system with just RMC sentences , if NTP has been updated to assume that YY (21) means 2021.
                                      Which i expect the unfold_century function does.

                                      /Bingo

                                      If you find my answer useful - Please give the post a 👍 - "thumbs up"

                                      pfSense+ 23.05.1 (ZFS)

                                      QOTOM-Q355G4 Quad Lan.
                                      CPU  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                      LAN  : 4 x Intel 211, Disk  : 240G SAMSUNG MZ7L3240HCHQ SSD

                                      1 Reply Last reply Reply Quote 0
                                      • J
                                        jcpingu @bingo600
                                        last edited by Jun 22, 2021, 7:16 PM

                                        @bingo600 said in Building a Stratum 1 NTP Server Using Odroid C2:

                                        ntp pool servers

                                        Does it matter where the ntp pool servers are inserted in the ntp.conf file?

                                        B 1 Reply Last reply Jun 22, 2021, 7:22 PM Reply Quote 0
                                        • B
                                          bingo600 @jcpingu
                                          last edited by bingo600 Jun 22, 2021, 7:56 PM Jun 22, 2021, 7:22 PM

                                          @jcpingu

                                          This guy puts it after the drift file

                                          # Drift file to remember clock rate across restarts
                                          driftfile /var/lib/ntp/ntp.drift
                                          # Servers
                                          pool uk.pool.ntp.org iburst
                                          

                                          And have a look here
                                          https://lintut.com/how-to-verify-ntp-setup-is-working-properly-in-linux-or-unix-server/

                                          Verifying a stratum1 server might not be "super easy"

                                          Use
                                          ntpstat

                                          My box says (No GPS installed) :

                                          ntpstat
                                          synchronised to NTP server (80.71.132.xxx) at stratum 2 
                                             time correct to within 48 ms
                                             polling server every 1024 s
                                          
                                          

                                          And
                                          ntpq -p

                                          ntpq -p
                                               remote           refid      st t when poll reach   delay   offset  jitter
                                          ==============================================================================
                                          -n1.taur.xx      .PPS0.           1 u  753 1024  377    7.164   -0.397   0.383
                                          *80.71.132.10x.i .GPS.            1 u  985 1024  377    1.862   -0.114   0.111
                                          +mmo2.ntp.xx  .PPS.            1 u  141 1024  377    2.827   -0.571   0.479
                                           5.103.139.163.s .GPS.            1 u   8d 1024    0    3.267    0.348   0.000
                                          -82.180.61.122   193.204.114.233  2 u  735 1024  377   40.205    0.981   0.419
                                          +grape.inet.xx.n 68.166.61.255    2 u  315 1024  377    1.207   -0.107   0.089
                                          
                                          

                                          The peer with the * in front (here 80.71.132.10x.i ) is the one that is used (synced to) right now.

                                          o = pps peer
                                          * = sys peer
                                          # = too distant
                                          + = selected
                                          x = false ticker
                                          - = discarded
                                          
                                          

                                          Show the output of your ntpq -p

                                          If you find my answer useful - Please give the post a 👍 - "thumbs up"

                                          pfSense+ 23.05.1 (ZFS)

                                          QOTOM-Q355G4 Quad Lan.
                                          CPU  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                          LAN  : 4 x Intel 211, Disk  : 240G SAMSUNG MZ7L3240HCHQ SSD

                                          J 2 Replies Last reply Jun 22, 2021, 7:59 PM Reply Quote 0
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