3Com Switch 4800G 24-Port Configuration Manual page 969

Configuring NTP
Broadcast Mode with
Authentication
[SwitchB] display ntp-service sessions
source reference
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[12345] 1.0.1.11 127.127.1.0
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations :
Network requirements
Switch C's local clock is to be used as a reference source, with the stratum level
■
of 3.
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.
■
Network diagram
Figure 288 Network diagram for configuration of NTP broadcast mode with
authentication
Vlan -int3
1.0.1.11/24 1.0.1 .10 /24
Switch A
Configuration procedure
1 Configuration on Switch C:
# Specify the local clock as the reference source, with the stratum level of 3.
<SwitchC> system-view
[SwitchC] ntp-service refclock-master 3
# Configure NTP authentication
[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
stra reach poll
2 63
1
Vlan- int3 Vlan -int2
3.0.1.30 /24
Switch B
NTP Configuration Examples
now offset delay disper
64 3 -75.5 31.0
Vlan -int2
3.0.1.31 /24
Switch C
Vlan -int2
3.0.1.32/24
Switch D
969
16.5