3Com Switch 4500 Family Manual page 688

authentication-keyid key-id: Specifies the key ID used for sending packets to the NTP server. The
key-id argument ranges from 1 to 4294967295.
priority: Specifies the server identified by the remote-ip or the server-name argument as the preferred
server.
source-interface Vlan-interface vlan-id: Specifies an interface whose IP address serves as the source
IP address of NTP packets sent by the local switch to the server.
version number: Specifies the NTP version number. The number argument ranges from 1 to 3 and
defaults to 3.
Description
Use the ntp-service unicast-server command to configure an Ethernet switch to operate in the NTP
client mode.
Use the undo ntp-service unicast-server command to remove the configuration.
By default, no NTP operate mode is configured.
The remote server specified by remote-ip or server-name serves as the NTP server, and the local
switch serves as the NTP client. The clock of the NTP client will be synchronized by but will not
synchronize that of the NTP server.
Examples
# Configure the local switch to be synchronized to the NTP server with the IP address 128.108.22.44,
and set the version number to 3.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] ntp-service unicast-server 128.108.22.44 version 3
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