Ntp Servers And Peers - Safran SecureSync 2400 User Manual

2.15.8

NTP Servers and Peers

SecureSync can be configured to receive time from one or more available NTP
Servers (SecureSyncs or different models). This allows for NTP Servers on a tim-
ing network to be configured as potential (fallback) input time references for
SecureSync System Time synchronization. In the event that a current reference
becomes unavailable, SecureSync can fallback to the other NTP Servers available
on the network.
A group of NTP servers at the same Stratum level (Stratum 1 time servers, for
example) are considered as
NTP Servers at the same Stratum level
If SecureSync is configured to obtain time from other NTP Servers at the same
Stratum level (i.e., NTP Peers) but is currently using a different input reference as
its selected reference, SecureSync will report to the network (via the NTP time
stamps) that it is a Stratum 1 time server. Should, however, all input references
except the other NTP server(s) become unavailable, SecureSync will then drop to
a Stratum 2 time server (with System Time being derived from the NTP time
packets being received from the other NTP Peers.
Holdover
If SecureSync is synchronized to another NTP Server or reference, and that
server or reference subsequently loses sync or becomes unavailable (with no
other higher priority input references being present and valid), SecureSync will
then go into the
enabled and valid input reference becomes available again, or until the Holdover
period expires, whichever occurs first.
During Holdover mode, NTP will remain at the same Stratum level it was before
entering the Holdover mode and can continue to be the reference to the net-
work. However, if no input reference becomes available before the Holdover
period expires, Time Sync will be lost and shortly thereafter, NTP will report to
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external Stratum 1 NTP server will be used (unless its quality is determ-
ined to be low).
Note:
"weight" for NTP to select the GNSS input over other NTP
Servers.
5. Click the Submit
Holdover
If enabled, this function would give GPS additional
button.
NTP Peers to each other.
mode. It will remain in Holdover mode until any
2.15 Configure NTP
123