[Git][NTPsec/ntpsec][master] Documentation followup on the autonomy fix.

Eric S. Raymond gitlab at mg.gitlab.com
Wed Aug 30 15:16:39 UTC 2017


Eric S. Raymond pushed to branch master at NTPsec / ntpsec


Commits:
92daeed1 by Eric S. Raymond at 2017-08-30T11:15:52-04:00
Documentation followup on the autonomy fix.

- - - - -


16 changed files:

- docs/driver_arbiter.txt
- docs/driver_generic.txt
- docs/driver_jjy.txt
- docs/driver_modem.txt
- docs/driver_neoclock.txt
- docs/driver_oncore.txt
- docs/driver_spectracom.txt
- docs/driver_truetime.txt
- docs/ntpsec.txt
- ntpd/refclock_arbiter.c
- ntpd/refclock_generic.c
- ntpd/refclock_jjy.c
- ntpd/refclock_modem.c
- ntpd/refclock_neoclock.c
- ntpd/refclock_spectracom.c
- ntpd/refclock_truetime.c


Changes:

=====================================
docs/driver_arbiter.txt
=====================================
--- a/docs/driver_arbiter.txt
+++ b/docs/driver_arbiter.txt
@@ -15,8 +15,10 @@ This refclock is deprecated and obsolete. The NTPsec maintainers plan
 to remove it in a future release.  If you have a requirement for it,
 please make this known to us.
 
-This driver reports only two-digit years, and may thus be subject to
-both lingering Y2K effects and issues near future century rollovers.
+This driver reports only two-digit years, and is thus reliant on the
+system clock to be near correct before samples will be processed
+properly. You will not be able to use it to run autonomously, nor will
+it reliably recover from a trashed or zeroed system clock.
 
 == Description ==
 


=====================================
docs/driver_generic.txt
=====================================
--- a/docs/driver_generic.txt
+++ b/docs/driver_generic.txt
@@ -12,6 +12,15 @@ Reference ID: DCF | DCFa | DCFp | GPS | MSF
 Serial Port: /dev/refclock-'u'; TTY mode according to clock type
 PPS device: /dev/refclockpps-'u'; alternate PPS device
 
+== Warning ==
+
+Most modes of this driver report only two-digit years, and are thus
+reliant on the system clock to be near correct before samples will be
+processed properly. You will not be able to use these modes to run
+autonomously, nor will they reliably recover from a trashed or zeroed
+system clock.  The only exceptions are the Schweitzer 240x and the
+Trimble TAIP/TSIP modes.
+
 == Description ==
 
 The generic driver supports many different clock


=====================================
docs/driver_jjy.txt
=====================================
--- a/docs/driver_jjy.txt
+++ b/docs/driver_jjy.txt
@@ -7,11 +7,15 @@ Name: jjy
 Reference ID: JJY
 Serial Port: +/dev/jjyu+; See corresponding receiver
 
-== Description ==
+== Warning ==
+
+Some modes of this driver report only two-digit years, and are thus
+reliant on the system clock to be near correct before samples will be
+processed properly. You will not be able to use them to run
+autonomously, nor will it reliably recover from a trashed or zeroed
+system clock.
 
-Warning: some modes of this driver report only two-digit years, and
-may thus be subject to both lingering Y2K effects and problems near
-future century rollovers.
+== Description ==
 
 This driver supports the following the JJY receivers and the GPS clock
 sold in Japan, and the time service through a telephone line.


=====================================
docs/driver_modem.txt
=====================================
--- a/docs/driver_modem.txt
+++ b/docs/driver_modem.txt
@@ -9,11 +9,15 @@ xSerial Port: /dev/modem__u__; 9600 8N1
 Features: tty_clk
 Requires: a dial-out device.
 
-== Description ==
+== Warning ==
+
+The ACTS mode of this driver reports only two-digit years, and is thus
+reliant on the system clock to be near correct before samples will be
+processed properly. You will not be able to use it to run
+autonomously, nor will it reliably recover from a trashed or zeroed
+system clock.
 
-Warning: the ACTS mode of this driver reports only two-digit years,
-and may thus be subject to both lingering Y2K effects and problems
-near future century rollovers.
+== Description ==
 
 This driver supports the US (NIST and USNO) and European (PTB (Germany),
 NPL (UK), etc.) modem time services, as well as Spectracom GPS receivers


=====================================
docs/driver_neoclock.txt
=====================================
--- a/docs/driver_neoclock.txt
+++ b/docs/driver_neoclock.txt
@@ -9,11 +9,14 @@ Serial Port: /dev/neoclock4x-u
 
 image:pic/neoclock4x.gif[float="right",link="http://www.linum.com"]
 
-== Description ==
+== Warning ==
+
+This driver reports only two-digit years, and is thus reliant on the
+system clock to be near correct before samples will be processed
+properly. You will not be able to use it to run autonomously, nor will
+it reliably recover from a trashed or zeroed system clock.
 
-Warning: the ACTS mode of this driver reports only two-digit years,
-and may thus be subject to both lingering Y2K effects and problems
-near future century rollovers.
+== Description ==
 
 The refclock_neoclock4x driver supports the NeoClock4X receiver
 available from http://www.linum.com[Linum Software GmbH]. The receiver


=====================================
docs/driver_oncore.txt
=====================================
--- a/docs/driver_oncore.txt
+++ b/docs/driver_oncore.txt
@@ -15,8 +15,10 @@ been end-of-lifed. The NTPsec maintainers plan to remove it in a
 future release.  If you have a requirement for it, please make this
 known to us.
 
-This driver reports only two-digit years, and may thus be subject to
-both lingering Y2K effects and issues near future century rollovers.
+This driver reports only two-digit years, and is thus reliant on the
+system clock to be near correct before samples will be processed
+properly. You will not be able to use it to run autonomously, nor will
+it reliably recover from a trashed or zeroed system clock.
 
 == Description ==
 


=====================================
docs/driver_spectracom.txt
=====================================
--- a/docs/driver_spectracom.txt
+++ b/docs/driver_spectracom.txt
@@ -15,8 +15,10 @@ This refclock is deprecated and obsolete. The NTPsec maintainers plan
 to remove it in a future release.  If you have a requirement for it,
 please make this known to us.
 
-This driver reports only two-digit years, and may thus be subject to
-both lingering Y2K effects and issues near future century rollovers.
+This driver reports only two-digit years, and is thus reliant on the
+system clock to be near correct before samples will be processed
+properly. You will not be able to use it to run autonomously, nor will
+it reliably recover from a trashed or zeroed system clock.
 
 == Description ==
 


=====================================
docs/driver_truetime.txt
=====================================
--- a/docs/driver_truetime.txt
+++ b/docs/driver_truetime.txt
@@ -14,8 +14,10 @@ This refclock is deprecated and obsolete. The NTPsec maintainers plan
 to remove it in a future release.  If you have a requirement for it,
 please make this known to us.
 
-This driver reports only two-digit years, and may thus be subject to
-both lingering Y2K effects and issues near future century rollovers.
+This driver reports only two-digit years, and is thus reliant on the
+system clock to be near correct before samples will be processed
+properly. You will not be able to use it to run autonomously, nor will
+it reliably recover from a trashed or zeroed system clock.
 
 == Description ==
 


=====================================
docs/ntpsec.txt
=====================================
--- a/docs/ntpsec.txt
+++ b/docs/ntpsec.txt
@@ -157,6 +157,13 @@ codebase has been outright removed, with less than 5% new code added.
   rather than microseconds; this might actually matter for GPSDOs
   and high-quality radio clocks.
 
+* For a driver that ships 4-digit year stamps (notably including the NMEA
+  driver) that data is no longer ignored in favor of deducing the year
+  from the system clock.  This means that (a) it is now possible for
+  ntpd using a local clock source to recover from a trashed or zeroed
+  system clock (e.g. at boot time on a system with missing or damaged
+  vattery back up) without requiring sync to a remote peer.
+
 [[clients]]
 == Client Tool Improvements ==
 


=====================================
ntpd/refclock_arbiter.c
=====================================
--- a/ntpd/refclock_arbiter.c
+++ b/ntpd/refclock_arbiter.c
@@ -18,6 +18,9 @@
  * The claimed accuracy of this clock is 100 ns relative to the PPS
  * output when receiving four or more satellites.
  *
+ * WARNING: This driver depends on the system clock for year disambiguation.
+ * It will thus not be usable for recovery if the system clock is trashed.  
+ *
  * The receiver should be configured before starting the NTP daemon, in
  * order to establish reliable position and operating conditions. It
  * does not initiate surveying or hold mode. For use with NTP, the


=====================================
ntpd/refclock_generic.c
=====================================
--- a/ntpd/refclock_generic.c
+++ b/ntpd/refclock_generic.c
@@ -15,6 +15,11 @@
  * code in the parse library could also be dropped.
  * Also see subtypes 3 and 4, for which no information in use since 1999 and
  * 2001 respectively can be found on the web.
+ *
+ * WARNING: Most modes of this driver depend on the system clock for
+ * year disambiguation.  They will thus not be usable for recovery if
+ * the system clock is trashed. The only exceptions are the Scheitzer 240x
+ * and the two Trimble devices.
  */
 
 #include "config.h"


=====================================
ntpd/refclock_jjy.c
=====================================
--- a/ntpd/refclock_jjy.c
+++ b/ntpd/refclock_jjy.c
@@ -1,5 +1,9 @@
 /*
  * refclock_jjy - clock driver for JJY receivers
+ *
+ * WARNING: Some modes of this driver depend on the system clock for
+ * year disambiguation.  They will thus not be usable for recovery if
+ * the system clock is trashed.
  */
 
 /**********************************************************************/


=====================================
ntpd/refclock_modem.c
=====================================
--- a/ntpd/refclock_modem.c
+++ b/ntpd/refclock_modem.c
@@ -24,6 +24,10 @@
  * use as backup when neither a radio clock nor connectivity to Internet
  * time servers is available.
  *
+ * WARNING: The ACTS mode of this driver depends on the system clock
+ * for year disambiguation.  It will thus not be usable for recovery
+ * if the system clock is trashed.
+ *
  * This driver requires a modem with a Hayes-compatible command set
  * and control over the modem data terminal ready (DTR) control
  * line. The default modem setup string is hard-coded in the driver


=====================================
ntpd/refclock_neoclock.c
=====================================
--- a/ntpd/refclock_neoclock.c
+++ b/ntpd/refclock_neoclock.c
@@ -29,6 +29,10 @@
 #define DESCRIPTION	"NeoClock4X"
 
 /*
+ * WARNING: This driver depends on the system clock for year
+ * disambiguation.  It will thus not be usable for recovery if the
+ * system clock is trashed.
+ *
  * If you want the driver for whatever reason to not use
  * the TX line to send anything to your NeoClock4X
  * device you must tell the NTP refclock driver which


=====================================
ntpd/refclock_spectracom.c
=====================================
--- a/ntpd/refclock_spectracom.c
+++ b/ntpd/refclock_spectracom.c
@@ -22,6 +22,9 @@
  * This driver supports the "Type 2" format emitted by Spectracom time
  * servers including the 9483, 9489, and SecureSync.
  *
+ * WARNING: This driver depends on the system clock for year disambiguation.
+ * It will thus not be usable for recovery if the system clock is trashed.  
+ *
  * In former times this driver supported the Spectracom 9300 (now
  * end-of-lifed) and several models of Spectracom radio clocks that were
  * obsolesced by the WWVB modulation change at 2012-10-29T15:00:00Z.


=====================================
ntpd/refclock_truetime.c
=====================================
--- a/ntpd/refclock_truetime.c
+++ b/ntpd/refclock_truetime.c
@@ -41,6 +41,9 @@
  *	XL-DC:		(a 151-602-210, reported by the driver as a GPS/TM-TMD)
  *	GPS-800 TCU:	(an 805-957 with the RS232 Talker/Listener module)
  *
+ * WARNING: This driver depends on the system clock for year disambiguation.
+ * It will thus not be usable for recovery if the system clock is trashed.  
+ *
  * Most of this code is originally from refclock_wwvb.c (now 
  * refclock_spectracom.c) with thanks.
  * It has been so mangled that wwvb is not a recognizable ancestor.



View it on GitLab: https://gitlab.com/NTPsec/ntpsec/commit/92daeed155587106da07e158ccf072353e4af29f

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View it on GitLab: https://gitlab.com/NTPsec/ntpsec/commit/92daeed155587106da07e158ccf072353e4af29f
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