Spectracom VelaSync 1225, User Manual

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How long will the unit remain in Holdover mode?
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
synchronization.
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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