CLI Reference Guide-R04

Chapter 1 | Initial Switch Configuration
Setting the System Clock
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Configuring NTP Requesting the time from a an NTP server is the most secure method. You can
enable NTP authentication to ensure that reliable updates are received from only
authorized NTP servers. The authentication keys and their associated key number
must be centrally managed and manually distributed to NTP servers and clients.
The key numbers and key values must match on both the server and client.
When more than one time server is configured, the client will poll all of the time
servers, and compare the responses to determine the most reliable and accurate
time update for the switch.
To configure NTP time synchronization, enter commands similar to the following.
Console(config)#ntp client
Console(config)#ntp authentication-key 45 md5 thisiskey45
Console(config)#ntp authenticate
Console(config)#ntp server 192.168.3.20
Console(config)#ntp server 192.168.3.21
Console(config)#ntp server 192.168.5.23 key 19
Console(config)#exit
Console#show ntp
Current Time : Aug 17 11:28:16 2018
Current Mode : unicast
NTP Status : Enabled
NTP Authenticate Status : Enabled
NTP Server 192.168.3.20 version 4
NTP Server 192.168.3.21 version 4
NTP Server 192.168.5.23 version 4 key 19
NTP Authentication Key 45 md5 72P36P71R65V5930Q73Q6317747M6K1
Console#