Orolia SecureSync 2400 User Manual

and the availability of the time outputs is not immediately lost when input references are
no longer available.
While SecureSync is in Holdover, the only difference is the Holdover and associated Minor
alarm are asserted. There are no changes to NTP or any of the other outputs, i.e. while in
Holdover mode, NTP inside SecureSync continues to be at the same Stratum level it was
at before going into Holdover mode (such as Stratum1 when synced to GPS). Should the
Holdover period expire, however, or the unit is rebooted, the NTP Stratum will go to 16,
preventing any clients from being able to sync with SecureSync until GPS or another ref-
erence has been restored.
How long will the unit remain in Holdover mode?
SecureSync 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), SecureSync exits the Holdover mode and
returns to its fully synchronized state.
b.
The Holdover Timeout period expires. In this case, SecureSync 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 SecureSync 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, SecureSync will
then go back into Holdover mode.
What is "Holdover Timeout"?
Holdover Timeout is the user-configurable allowable time period in which SecureSync
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:
3.4 Holdover Mode
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Orolia SecureSync 2400 Specifications

General

Brand	Orolia
Model	SecureSync 2400
Category	Recording Equipment
Language	English