[ntp:questions] NMEA driver using common PPSAPI code

Venu Gopal neo.venu at gmail.com
Fri Oct 1 10:52:55 UTC 2010

Hello Dave,

1. NTP configuration:

server mode 24 minpoll 4 maxpoll 4
fudge flag1 1
fudge flag2 0
fudge flag3 1

driftfile /etc/ntp.drift
statsdir /var/log/ntp/

logfile /var/log/ntp/ntp.log
logconfig +all

statistics loopstats peerstats clockstats
filegen peerstats file peers type day link enable
filegen loopstats file loops type day link enable
filegen clockstats file clocks type day link enable


2. NTP was restarted intentionally to reflect the problem.
Assuming that once the time is set properly I wonder why
NTP resets the system clock by 0.3 seconds when restarted.

3. To verify if the problem is due to the handling of different times (UTC &
NMEA driver was modified to ignore ZDG messages. As per the configuration
shown above only ZDA messages are being used.

4. I feel that this problem might be related to the usage PPSAPI common
since it never occurs in the earlier versions of NTP using local PPSAPI.

5. I'll try with kernel PPS disabled and setting the appropriate fudge flags
let you know the behavior.

Thanks & Kind Regards,

More information about the questions mailing list