Administrator's Guide

Time of Day Clock Synchronization
Issue 5 October 2002 1889555-233-506
Use of Time of Day information by MultiVantage
MultiVantage features use the time of day information for a variety of reasons.
■ Time stamp data elements (CDR records, error logs, Message Sequence
Trace data, MCT records, BCMS, and CMS data)
■ Set time-out intervals (Automatic wakeup messages, Do no disturb
intervals)
■ Schedule tasks (scheduled maintenance, moving CDR data to the output
file)
■ Synchronize time of day information with other processors (periodic TOD
messages sent to the 860 processor on the S8100 Media Server processor
circuit pack)
The time of day value used for the MultiVantage system time is essentially local
time with or without daylight savings time adjustments.
S8100 Media Server uses the Windows 2000 and S8700 Multi-Connect uses
LINUX as the platform operating system. The use of the system clock from the
platform OS is transparent. Both Windows and LINUX use UTC for the system
(software) clock. Library functions and APIs are used to express the time in local
time. MultiVantage code still uses local time. However, the daylight savings rule
for system time is controlled by the OS. This is accounted for by using the time
adjustments from the OS for Daylight Savings Rule 1. The display of this rule on
the System Access Terminal Daylight Savings Rules screen is display-only. The
values displayed for the time adjustments are read from the operating system.
In legacy DEFINITY when a change is made to the system time because of a
manual change on the Set Time SAT screen or because of an adjustment for
daylight savings time, certain DEFINITY applications that need to know about
the change are notified before the change is made to the system clock.
If you do not have Internet access, you can continue to manually set the time of
day.
!
CAUTION:
Avoid setting the time manually while the TOD clock sync feature is enabled.
Manually setting the time, while NTP/SNTP is running, defeats the purpose
of synching the UTC time and could cause problems depending on the
difference between the system time and UTC.