3Com 4500 PWR 26-Port Configuration Manual page 666

To synchronize Device B, you need to perform the following configurations on Device A.
# Enable the NTP authentication function.
<DeviceA> system-view
[DeviceA] ntp-service authentication enable
# Configure an MD5 authentication key, with the key ID being 42 and the key being aNiceKey.
[DeviceA] ntp-service authentication-keyid 42 authentication-mode md5 aNiceKey
# Specify the key 42 as a trusted key.
[DeviceA] ntp-service reliable authentication-keyid 42
(After the above configurations, the clock of Device B can be synchronized to that of Device A.) View the
status of Device B after synchronization.
[DeviceB] display ntp-service status
Clock status: synchronized
Clock stratum: 3
Reference clock ID: 1.0.1.11
Nominal frequence: 100.0000 Hz
Actual frequence: 100.1000 Hz
Clock precision: 2^18
Clock offset: 0.66 ms
Root delay: 27.47 ms
Root dispersion: 208.39 ms
Peer dispersion: 9.63 ms
Reference time: 17:03:32.022 UTC Apr 2 2007 (BF422AE4.05AEA86C)
The output information indicates that the clock of Device B is synchronized to that of Device A, with a
clock stratum level of 3, one stratum level lower than that Device A.
# View the information about NTP sessions of Device B (you can see that a connection is established
between Device B and Device A).
<DeviceB> display ntp-service sessions
source
*************************************************************************
1.0.1.11 127.127.1.0
note: 1 source(master),2 source(peer),3 selected,4 candidate,5 configured
Total associations :
reference stra reach poll
2 255 64
1
54-22
now offset
8 2.8 17.7 1.2
delay disper
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