3com S7906E Installation Instruction
1-25
Nominal frequency: 100.0000 Hz
Actual frequency: 100.0000 Hz
Clock precision: 2^18
Clock offset: 0.0000 ms
Root delay: 31.00 ms
Root dispersion: 1.05 ms
Peer dispersion: 7.81 ms
Reference time: 14:53:27.371 UTC Sep 19 2005 (C6D94F67.5EF9DB22)
As shown above, Device B has been synchronized to Device A, and the clock stratum level of Device B
is 3, while that of Device A is 2.
# View the NTP session information of Device B, which shows that an association has been set up
Device B and Device A.
[DeviceB] display ntp-service sessions
source reference stra reach poll now offset delay disper
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[12345] 1.0.1.11 127.127.1.0 2 63 64 3 -75.5 31.0 16.5
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations : 1
Configuring NTP Broadcast Mode with Authentication
Network requirements
z
Switch C’s local clock is to be used as a reference source, with the stratum level of 3.
z
Switch C works in the broadcast server mode and sends out broadcast messages from
VLAN-interface 2.
z
Switch D works in the broadcast client mode and receives broadcast messages through
VLAN-interface 2.
z
NTP authentication is enabled on both Switch C and Switch D.
Figure 1-12 Network diagram for configuration of NTP broadcast mode with authentication
Vlan-int3
1.0.1.11/24
1.0.1.11/24
Vlan-int3
1.0.1.10/24
Vlan-int2
3.0.1.31/24
Vlan-int2
3.0.1.32/24
Vlan-int2
3.0.1.30/24
3.0.1.30/24
Switch A
Switch B
Switch C
Switch D
Configuration procedure
1) Configuration on Switch C:
# Specify the local clock as the reference source, with the stratum level of 3.