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# Specify Device A as the NTP server.
[DeviceB] ntp-service unicast-server 1.0.1.11 authentication-keyid 42
Before Device B can synchronize its clock to that of Device A, you need to enable NTP authentication
for Device A.
Perform the following configuration on Device A:
# Enable NTP authentication.
[DeviceA] ntp-service authentication enable
# Set an authentication key.
[DeviceA] ntp-service authentication-keyid 42 authentication-mode md5 aNiceKey
# Specify the key as a trusted key.
[DeviceA] ntp-service reliable authentication-keyid 42
# View the NTP status of Device B after clock synchronization.
[DeviceB] display ntp-service status
Clock status: synchronized
Clock stratum: 3
Reference clock ID: 1.0.1.11
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
**************************************************************************
[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.