Directing Responses From Ntp Servers; Refusing Broadcasts From Ntp Servers - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - SYSTEM BASICS CONFIGURATION GUIDE 2010-10-04 Configuration Manual

ping
ntp source
access-list
Copyright © 2010, Juniper Networks, Inc.
Use to assign an NTP server to the system and to customize the way the server
communicates with the system.
Specify the source option to direct responses from the NTP server to a specific interface
on the system and override the ntp source command.
Example
host1(config)#ntp server 192.35.42.1 version 3 prefer source atm 3/0.1
Use the no version to terminate communications between the system and an NTP
server.
See ntp server.
Use to check that the system can reach an NTP server.
Example
host1(config)#ping 192.35.42.1
There is no no version.
See ping.

Directing Responses from NTP Servers

By default, an NTP server sends a response to the interface from which an NTP request
originated. You can now direct responses from all NTP servers to one interface on the
system or direct responses from a specific NTP server to a specific interface.
Use to direct responses from all NTP servers to a specific interface. Using the source
option with the ntp server command overrides the ntp source command.
Example
host1(config)#ntp source atm 3/1
Use the no version to direct all servers to reply to the interface from which the NTP
request was sent (the default setting).
See ntp source.

Refusing Broadcasts from NTP Servers

You can prevent the system from receiving certain types of broadcasts and specify the
servers from which the system will accept NTP broadcasts. To do so:
Issue the ntp access-group command.
1.
Configure an access list.
2.
Chapter 10: Configuring the System Clock
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