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NTP error on NetScreen after DST change



Article ID: KB8077 KB Last Updated: 11 Aug 2010Version: 3.0

NetScreen Firewalls support standard RFC NTP which returns time in UTC format only. As an effect ScreenOS does not support NTP servers that use various timezones and DST.


If the NTP server is returning time as per its local time zone this could create sync issues after DST changes. You will see the following 531 Notification type message in the log

system-notification-00531: Network Time Protocol adjustment of ------ ms from NTP server primary exceeds the allowed adjustment of ----- ms.

NOTE : UTC = Coordinated Universal Time (abbreviated as UTC, and therefore often spelled out as Universal Time Coordinated and sometimes as Universal Coordinated Time) is the standard time common to every place in the world. Formerly and still widely called Greenwich Mean Time (GMT) and also World Time, UTC nominally reflects the mean solar time along the Earth's prime meridian. The prime meridian is arbitrarily based on the meridian that runs through the Greenwich Observatory outside of London, where the present system originated. The UTC is based on an atomic clock to which adjustments of a second (called a leap second) are sometimes made to allow for variations in the solar cycle. This time does not accomodate Day Light Saving time.



To fix it you need to either manually sync to NTP or have the NTP server return value in UTC format only.

exec ntp update

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