3Com SuperStack 4 Configuration Manual page 355

Configure NTP Broadcast
Mode
By this time, Switch 4 has been synchronized by Switch 5 and it is at stratum 2, or
higher than Switch 5 by 1.
Display the sessions of Switch 4 and you will see Switch 4 has been connected
with Switch 5.
[switch4]display ntp-service sessions
source
*******************************************************************
[12345]3.0.1.33 LOCAL(0) 2
note: 1 source(master),2 source(peer),3 selected,4 candidate,5
configured
Network Requirements
On Switch 3, set local clock as the NTP master clock at stratum 2 and configure to
broadcast packets from Vlan-interface2. Configure Switch 4 and Switch 1 to listen
to the broadcast from their Vlan-interface2 respectively. Networking Diagram
See Figure 94.
Configuration Procedure
Configure Switch 3:
1 Enter System View.
<switch3> system-view
2 Set the local clock as the NTP master clock at stratum 2.
[switch3]ntp-service refclock-master 2
3 Enter Vlan-interface2 view.
[switch3]interface vlan-interface 2
4 Set it as broadcast server.
[switch3-Vlan-Interface2]ntp-service broadcast-server
Configure Switch 4:
1 Enter System View.
<switch4> system-view
2 Enter Vlan-interface2 view.
[switch4]interface vlan-interface 2
[switch4-Vlan-Interface2]ntp-service broadcast-client
Configure Switch 1:
1 Enter System View.
<switch1> system-view
2 Enter Vlan-interface2 view.
[switch1]interface vlan-interface 2
[switch1-Vlan-Interface2]ntp-service broadcast-client
reference stra reach poll
377
Typical NTP Configuration Examples
now offset
64 16 0.0
367
delay disper
0.0 0.9