Orolia Spectracom VelaSync 1232, User Manual

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VelaSync will remain in Holdover mode until either:
a.
Any enabled and valid input reference becomes available again: If one or more ref-
erences return and are declared valid before the Holdover period has expired (even
momentarily, i.e. for at least one second), VelaSync exits the Holdover mode and
returns to its fully synchronized state.
b.
The Holdover Timeout period expires. In this case, VelaSync will declare loss of syn-
chronization.
Note that Holdover mode does not persist through reboots or power cycles. If a reboot or
power cycle occurs while VelaSync is in Holdover mode, it will power-up and remain in a
“
not synchronized ” state until at least one valid Time and 1PPS input reference becomes
available again. While in this state, NTP will be Stratum 15 and outputs will not be usable. If
the input references are restored and then lost or declared not valid again, VelaSync will
then go back into Holdover mode.
What is "Holdover Timeout"?
Holdover Timeout is the user- configurable allowable time period in which VelaSync
remains in Holdover mode before it declares loss of synchronization. Holdover Timeout can
be adjusted according to application-specific requirements and preferences. See below for
recommendations on how long (short) the Holdover Timeout should be.
How to configure Holdover Timeout
To set the Holdover Timeout value:
Navigate to MANAGEMENT > OTHER: Disciplining , and click the GEAR icon in the
Status panel:
3.3 Managing References
CHAPTER
3
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