HP 4800G Series Configuration Manual page 1912

Switch C works in the broadcast server mode and sends out broadcast messages from
VLAN-interface 2.
Switch D works in the broadcast client mode and receives broadcast messages through
VLAN-interface 2.
NTP authentication is enabled on both Switch C and Switch D.
Figure 1-12 Network diagram for configuration of NTP broadcast mode with authentication
Configuration procedure
1) Configuration on Switch C:
# Configure NTP authentication.
<SwitchC> system-view
[SwitchC] ntp-service authentication enable
[SwitchC] ntp-service authentication-keyid 88 authentication-mode md5 123456
[SwitchC] ntp-service reliable authentication-keyid 88
# Specify Switch C as an NTP broadcast server, and specify an authentication key.
[SwitchC] interface vlan-interface 2
[SwitchC-Vlan-interface2] ntp-service broadcast-server authentication-keyid 88
2) Configuration on Switch D:
# Configure NTP authentication.
<SwitchD> system-view
[SwitchD] ntp-service authentication enable
[SwitchD] ntp-service authentication-keyid 88 authentication-mode md5 123456
[SwitchD] ntp-service reliable authentication-keyid 88
# Configure Switch D to work in the NTP broadcast client mode.
[SwitchD] interface vlan-interface 2
[SwitchD-Vlan-interface2] ntp-service broadcast-client
Now, Switch D can receive broadcast messages through VLAN-interface 2, and Switch C can send
broadcast messages through VLAN-interface 2. Upon receiving a broadcast message from Switch C,
Switch D synchronizes its clock to that of Switch C.
# View the NTP status of Switch D after clock synchronization.
[SwitchD-Vlan-interface2] display ntp-service status
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