r6 - 2007-05-05 - 16:45:19 - SteveKosteckeYou are here: NTP >  Support Web > ConfiguringNTP > ConfiguringRefclocks > ConfiguringMotorolaOncoreRefclocks
NTP users are strongly urged to take immediate action to ensure that their NTP daemons are not susceptible to being used in distributed denial-of-service (DDoS) attacks. Please also take this opportunity to defeat denial-of-service attacks by implementing Ingress and Egress filtering through BCP38.

ntp-4.2.8p12 was released on 14 August 2018. It addresses 1 low-/medium-severity security issue in ntpd, 1 low-severity security issue in ntpq and ntpdc, and provides 27 non-security bugfixes and 4 other improvements over 4.2.8p11.

Please see the NTP Security Notice for vulnerability and mitigation details.

Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
REFACTOR See ConfiguringMotorolaOncoreRefclocksDev for discussion of this topic.

6.1.11. Configuring Motorola ONCORE Refclocks

I try to summarize the necessary steps to set up an M12+T for precision timing using:

  1. Set Position-Hold position, either:
    • Manually: If the Antenna position is known the user can specify the coordinates by the @@As command.
    • Using Autosurvey: The mode 3 in @@Gd command will automatically average 10,000 position fixes and then force the receiver into Postion-Hold. This operation can take some hours. To check if the receiver is in Position-Hold mode, the bit 4 ("AutoSurvey Mode" of the @@Ha or @@Hb command has to be set 00, during averaging has value 01).
  2. Set Cable delay with command @@Az: In our case the a cable of 5 meters means a delay of 25ns. After sending this command we guess the time included in the @@Hb answer is time automatic corrected of cable delay.
  3. Set the Timing Parameters by the commands:
    • @@Gf: This message is used to set the T-RAIM alarm limit (between 300 and 1,000,000ns).
    • @@Ge: This message is used to turn the T-RAIM function on.
    • @@Hn: The @@Hn T-RAIM Status Message to get status strings that alert to any alarm conditions.

Richard Gilbert says:

Assuming that your version of NTP was built with the ONCORE refclock driver, you should be able to connect your Motorola Oncore GT+ to a serial port and configure it as directed by the documentation for that version! I've only configured an Oncore on ntpd 4.2.0 which requires two links:

  • /dev/oncore.pps.0
  • /dev/oncore.serial.0

pointing to your serial port.

Next you need /etc/ntp.oncore0 which is configuration file that looks something like this:

# /etc/ntp.oncore0
#
# Reference Clock configuration for Motorola Oncore M12
#
# Five Choices for MODE
#    (0) ONCORE is preinitialized, don't do anything to change it.
#          nb, DON'T set 0D mode, DON'T set Delay, position...
#    (1) NO RESET, Read Position, delays from data file, lock it in, go to 0D mode.
#    (2) NO RESET, Read Delays from data file, do SITE SURVEY to get position,
#                  lock this in, go to 0D mode.
#    (3) HARD RESET, Read Position, delays from data file, lock it in, go to 0D mode.
#    (4) HARD RESET, Read Delays from data file, do SITE SURVEY to get position,
MODE 1
#     NB. If a POSITION is specified in the config file with mode=(2,4) 
[SITE SURVEY]
#         then this position is set as the INITIAL position of the ONCORE.
#         This can reduce the time to first fix.
LAT 39 45.3753          # Positive is North.
LONG -75 04.27187       # Negative is West
HTGPS 18.28 M           # Height in meters.
SHMEM  /var/log/ntpstats/ONCORE.0
TRAIM YES               # May need this if antenna position is suboptimal.

Finally, you need to add a server statement in /etc/ntp.conf:

# Reference Clock (Motorola Oncore M12)
server 127.127.30.0 prefer

All this stuff is, AFAIK, version specific. What I have shown here is working on a Sun Ultra 10 running Solaris 8.

Your mileage may vary.

Related Topics: MotorolaOncoreRefclockUsers

Edit | WYSIWYG | Attach | Printable | Raw View | Backlinks: Web, All Webs | History: r6 < r5 < r4 < r3 < r2 | More topic actions
 
SSL security by CAcert
Get the CAcert Root Certificate
This site is powered by the TWiki collaboration platform
IPv6 Ready
Copyright & 1999-2018 by the contributing authors. All material on this collaboration platform is the property of the contributing authors. Ideas, requests, problems regarding the site? Send feedback