3com 3031 Instruccion De Instalación

The interface is determined by the 

 or the 

. The source IP addresses in the packets are obtained from the 

interface. If the command 

 or 

 has specified the transmitting interface, it will be taken as the 

transmitting interface. 

The following configuration is used to set the external reference clock or the local 
clock to be the NTP master clock.

Perform the following in the System View.

The parameter 

X.X.X.X

 is the IP address of the reference clock, which is 

127.127.t.u. The stratum number of the NTP master clock can be specified. 

layers-number 

is used to specify the stratum number of the local clock, which is 

in the range of 1 to 15. When no IP address is specified, the local clock is the NTP 
master clock by default. 

The following configuration is used to enable or disable an interface to receive the 
NTP messages. 

Perform the following in the Interface View.

These configurations must be configured on the interface that is disabled/enabled 
to receive NTP messages. 

The following configuration is used to set the access authority of the NTP service 
of the local router. This is only a low level security approach. The more secure 
approach is to perform ID authentication. When there is an access request, this 
command can be used to make the matches in sequence in a way of from the 
minimum access authority to the maximum authority. All matches are based on 
the first match. The match order is 

, 

,

, 

. 

Remove the interface for the local to 
transmit NTP messages

Table 88   Setting the interface for the local to transmit NTP messages

Table 89   Setting external reference clock or local clock as NTP master clock

Set external reference clock or local clock as 
NTP master clock

ntp-service refclock-master [ 
X.X.X.X ] [ layers-number ]

Remove NTP master clock

undo ntp-service refclock-master [ 
X.X.X.X ]

Table 90   Enabling/disabling an interface to receive NTP messages 

Disable an interface to receive NTP 
messages

ntp-service in-interface disable

Enable an interface to receive NTP 
messages 

undo ntp-service in-interface disable