[ntp:questions] Leap second bug?

Spoon root at localhost.invalid
Wed Jan 9 17:10:17 UTC 2008


Spoon wrote:

> ntpd kicked my clock forward one second on January 1 at 00:19:38 UTC.
> 
> (My ntp.conf lists 12 servers. Delays range from 28 to 48 ms.)
> 
> Dec 31 23:25:39 offset 0.000329 sec freq -6.715 ppm error 0.000333 poll 8
> Dec 31 23:28:39 offset 0.000329 sec freq -6.715 ppm error 0.000340 poll 8
> Dec 31 23:31:39 offset 0.000329 sec freq -6.715 ppm error 0.000424 poll 8
> Dec 31 23:34:39 offset 0.000403 sec freq -6.714 ppm error 0.000493 poll 8
> Dec 31 23:37:39 offset 0.000270 sec freq -6.714 ppm error 0.000348 poll 8
> Dec 31 23:40:39 offset 0.000270 sec freq -6.714 ppm error 0.000337 poll 8
> Dec 31 23:43:39 offset 0.000268 sec freq -6.714 ppm error 0.000327 poll 8
> Dec 31 23:46:39 offset 0.000268 sec freq -6.714 ppm error 0.000381 poll 8
> Dec 31 23:49:39 offset 0.000268 sec freq -6.714 ppm error 0.000446 poll 8
> Dec 31 23:52:39 offset 0.000268 sec freq -6.714 ppm error 0.000446 poll 8
> Dec 31 23:55:39 offset 0.000268 sec freq -6.714 ppm error 0.000334 poll 8
> Dec 31 23:58:39 offset 0.000268 sec freq -6.714 ppm error 0.000317 poll 8
> Jan  1 00:01:38 offset 0.000268 sec freq -6.714 ppm error 0.000318 poll 8
> Jan  1 00:04:38 offset 0.000268 sec freq -6.714 ppm error 0.447285 poll 8
> Jan  1 00:06:47 synchronized to A, stratum 2
> Jan  1 00:07:38 offset -0.001068 sec freq -6.720 ppm error 0.632509 poll 8
> Jan  1 00:10:38 offset -0.001068 sec freq -6.720 ppm error 0.632509 poll 8
> Jan  1 00:13:38 offset -0.001068 sec freq -6.720 ppm error 0.774695 poll 8
> Jan  1 00:15:39 synchronized to H, stratum 1
> Jan  1 00:16:38 offset -0.001068 sec freq -6.720 ppm error 0.632382 poll 8
> +++++
> Jan  1 00:19:38 time reset +0.999402 s
> +++++
> Jan  1 00:19:38 system event 'event_clock_reset' (0x05) status 
> 'sync_alarm, sync_unspec, 15 events, event_peer/strat_chg' (0xc0f4)
> Jan  1 00:19:38 system event 'event_peer/strat_chg' (0x04) status 
> 'sync_alarm, sync_unspec, 15 events, event_clock_reset' (0xc0f5)
> Jan  1 00:19:39 offset 0.000000 sec freq -6.720 ppm error 0.447203 poll 4
> Jan  1 00:19:54 peer A event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:19:55 peer B event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:19:59 peer C event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:04 peer D event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:07 peer E event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:08 peer F event 'event_reach' (0x84) status 'unreach, conf, 
> 4 events, event_reach' (0x8044)
> Jan  1 00:20:14 peer G event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:18 peer H event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:24 peer I event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:26 peer J event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:28 peer K event 'event_reach' (0x84) status 'unreach, conf, 
> 2 events, event_reach' (0x8024)
> Jan  1 00:20:39 peer L event 'event_reach' (0x84) status 'unreach, conf, 
> 4 events, event_reach' (0x8044)
> Jan  1 00:20:55 synchronized to A, stratum 2
> Jan  1 00:20:55 system event 'event_sync_chg' (0x03) status 'leap_none, 
> sync_ntp, 15 events, event_peer/strat_chg' (0x6f4)
> Jan  1 00:20:55 system event 'event_peer/strat_chg' (0x04) status 
> 'leap_none, sync_ntp, 15 events, event_sync_chg' (0x6f3)
> Jan  1 00:21:22 synchronized to H, stratum 1
> 
> I also noticed that, the day before, the STA_INS (insert leap second) had
> been set and reset several times.
> 
> Dec 31 00:14:30 kernel time sync status change 0011
> Dec 31 00:27:21 kernel time sync status change 0001
> Dec 31 03:19:46 kernel time sync status change 0011
> Dec 31 03:52:30 kernel time sync status change 0001
> Dec 31 04:09:33 kernel time sync status change 0011
> Dec 31 04:35:11 kernel time sync status change 0001
> Dec 31 07:26:03 kernel time sync status change 0011
> Dec 31 07:47:28 kernel time sync status change 0001
> Dec 31 10:00:51 kernel time sync status change 0011
> Dec 31 10:17:01 kernel time sync status change 0001
> 
> (Apparently, the bit was not set when 2007 ended.)
> 
> Could this be a leap year bug? or did I just lose connectivity at the wrong
> time and it's just a coincidence?
> 
> # ntpq -crv
> assID=0 status=06f4 leap_none, sync_ntp, 15 events, event_peer/strat_chg,
> version="ntpd 4.2.4p0 at 1.1472 Fri Mar 16 10:45:43 UTC 2007 (1)",
> processor="i686", system="Linux/2.6.22.1-rt9", leap=00, stratum=3,
> precision=-20, rootdelay=30.293, rootdispersion=50.341, peer=39672,
> refid=145.238.203.10,
> reftime=cb262893.e5d244fd  Wed, Jan  2 2008 15:13:23.897, poll=8,
> clock=cb262c3b.dbe5d3de  Wed, Jan  2 2008 15:28:59.858, state=4,
> offset=0.081, frequency=-6.758, jitter=0.525, noise=0.521,
> stability=0.001

I've just noticed the output of dmesg.
Clock: inserting leap second 23:59:60 UTC
(on two different systems)

The strange part is that, on one system, the line does not show up
in kern.log, while on the second system, it does:

Jan  8 16:16:05 kernel: Clock: inserting leap second 23:59:60 UTC

Spooky...




More information about the questions mailing list