Dynabrade Dynabug 57810, User Manual

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•
NTP Client—NTP clients are synchronized to a primary or secondary NTP server. Clients
do not re-distribute this time data to other devices.
NOTE: The NTP subnet includes a number of widely accessible public primary
time servers that can be used as a network’s primary NTP server. Juniper
Networks strongly recommends that you authenticate any primary servers
you use.
Each device on your network can be configured to run in one or more of the following
NTP modes:
•
Broadcast Mode—One or more devices is set up to transmit time information to a
specified broadcast or multicast address. Other devices listen time sync packets on
these addresses. This mode is less accurate than the client/server mode.
• Client/Server Mode—Devices are organized hierarchically across the network in
client/server relationships.
NOTE: QFX devices cannot be act as NTP servers, only clients.
• Symmetric Active (peer) Mode—Two or more devices are configured as NTP server
peers to provide redundancy.
By default, if an NTP client time drifts so that the difference in time from the NTP server
exceeds 128 milliseconds, the NTP client is automatically stepped back into
synchronization. The NTP client will still synchronize with the server even if the offset
between the NTP client and server exceeds the 1000-second threshold. You can manually
request that a device synchronize with an NTP server by using the
set date ntp
operational
command on the router. On devices running Junos OS that have dual Routing Engines,
the backup Routing Engine synchronizes directly with the master Routing Engine.
For more details on the Network Time Protocol, go to the Network Time Foundation
website at
http://www.ntp.org
.
Copyright © 2014, Juniper Networks, Inc. 4
Time Management Administration Guide for Routing Devices