3Com Switch 4800G 24-Port Configuration Manual page 963

Clock precision: 2^7
Clock offset: -21.1982 ms
Root delay: 15.00 ms
Root dispersion: 775.15 ms
Peer dispersion: 34.29 ms
Reference time: 15:22:47.083 UTC Apr 20 2007 (C6D95647.153F7CED)
As shown above, Switch B has been synchronized to Switch C, and the clock
stratum level of Switch B is 2, while that of Switch C is 1.
# View the NTP session information of Switch B, which shows that an association
has been set up between Switch B and Switch C.
[SwitchB] display ntp-service sessions
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[245] 3.0.1.31
[1234] 3.0.1.33
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations :
Configuring NTP Network requirements
Broadcast Mode
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Network diagram
Figure 285 Network diagram for NTP broadcast mode configuration
Switch A
Configuration procedure
1 Configuration on Switch C:
# Specify the local clock as the reference source, with the stratum level of 2.
<SwitchC> system-view
[SwitchC] ntp-service refclock-master 2
source reference
127.127.1.0
LOCL
2
Switch C's local clock is to be used as a reference source, with the stratum level
of 2.
Switch C works in the broadcast server mode and sends out broadcast
messages from VLAN-interface 2.
Switch D and Switch A work in the broadcast client mode and listen to
broadcast messages through their respective VLAN-interface 2.
Vlan -int3 Vlan- int3
1.0.1.11/24 1.0.1 .10 /24
stra reach poll
2 15 64
1 14 64
3.0.1.31 /24
Vlan -int2
3.0.1.30 /24
Switch B
3.0.1.32/24
NTP Configuration Examples
now offset delay
24 10535.0 19.6
27 -77.0 16.0
Vlan -int2
Switch C
Vlan -int2
Switch D
963
disper
14.5
14.8