Time Protocols

SNTP: Viewing, Selecting, and Configuring

Figure 9-10. Example of SNTP with Time Synchronization Disabled

Disabling the SNTP Mode. If you want to prevent SNTP from being used even if selected by timesync (or the Menu interface’s Time Sync Method param­ eter), configure the SNTP mode as disabled.

Syntax: no sntpDisables SNTP by changing the SNTP mode configuration toDisabled.

For example, if the switch is running SNTP in Unicast mode with an SNTP server at 10.28.227.141 and a server version of 3 (the default), no sntp changes the SNTP configuration as shown below, and disables time synchronization on the switch.

Even though the Time Sync Mode is set to Sntp, time synchronization is disabled because no sntp has disabled the SNTP Mode parameter.

Figure 9-11. Example of Disabling Time Synchronization by Disabling the SNTP Mode

SNTP Client Authentication

Enabling SNTP authentication allows network devices such as HP ProCurve switches to validate the SNTP messages received from an NTP or SNTP server before updating the network time. NTP or SNTP servers and clients must be configured with the same set of authentication keys so that the servers can authenticate the messages they send and clients (HP ProCurve switches) can validate the received messages before updating the time.

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