3Com Switch 7750 Series
Command Reference Guide – NTP Chapter 1 NTP Configuration Commands
1-11
View
VLAN interface view
Parameter
ip-address: Specifies a multicast IP address of Class D and default to 224.0.1.1.
authentication-keyid: Specifies an authentication key.
keyid: Key ID used in multicast, ranging from 0 to 4,294,967,295.
ttl: Defines the time to live (TTL) of a multicast packet.
ttl-number: Specify the TTL of a multicast packet, ranging from 1 to 255.
version: Defines an NTP version number.
number: Specifies an NTP version number, ranging from 1 to 3.
Description
Use the ntp-service multicast-server command to configure NTP multicast server
mode. If no IP address is specified, the switch automatically chooses 224.0.1.1 as the
multicast IP address.
Use the undo ntp-service multicast-server command to disable NTP multicast
server mode, if no IP address is specified, the switch will disable the configuration of
the multicast IP address 224.0.1.1.
By default, the multicast service is disabled. IP address defaults to 224.0.1.1 and the
version number defaults to 3.
Designate an interface on the local device to transmit NTP multicast packets. The local
device operates in multicast-server mode and multicasts packets regularly to its
clients.
Example
# Configure to transmit NTP multicast packets encrypted with Key 4 through
VLAN-interface 1 at 224.0.1.1 and use NTP version 3.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] interface vlan-interface 1
[3Com-Vlan-Interface1] ntp-service multicast-server 224.0.1.1
authentication-keyid 4 version 3
1.1.14 ntp-service refclock-master Syntax
ntp-service refclock-master [ ip-address ] [ stratum ]
undo ntp-service refclock-master [ ip-address ]