3Com Switch 8800 Advanced Software V5 Configuration Guide

1072 CHAPTER 85: NTP CONFIGURATION
Configuring the Local
Clock as a Reference
Source
A network device can get its clock synchronized in one of the following two ways:
■ Synchronized to the local clock, which as the reference source.
■ Synchronized to another device on the network in any of the four NTP
operation modes previously described.
If you configure two synchronization modes, the device will choose the optimal
clock as the reference source.
Follow these steps to configure the local clock as a reference source:
n
In this command, ip-address must be 127.127.1.u, where u ranges from 0 to 3,
representing the NTP process ID.
Configuring Optional
Parameters of NTP
Configuring the
Interface to Send NTP
Messages
After you specify the interface used to send NTP messages, the source IP address
of the NTP message will be configured as the primary IP address of the specified
interface.
Following these steps to configure the local interface used to send NTP messages:
c
CAUTION: If you have specified an interface in the ntp-service unicast-server or
ntp-service unicast-peer command, this interface will be used for sending NTP
messages.
Disabling an Interface
from Receiving NTP
Messages
Follow these steps to disable an interface from receiving NTP messages:
To do... Use the command... Remarks
Enter system view system-view -
Configure the local clock as a
reference source
ntp-service refclock-master
[ ip-address ] [ stratum ]
Required
To do... Use the command... Remarks
Enter system view system-view -
Configure the interface used
to send NTP messages
ntp-service
source-interface
interface-type
interface-number
Required
To do... Use the command... Remarks
Enter system view system-view -
Enter interface view interface interface-type
interface-number
Required
Disable the interface from
receiving NTP messages
ntp-service in-interface
disable
Required
An interface is enabled to
receive NTP messages by
default