Objective

Simple Network Time Protocol (SNTP) is the simplified version of Network Time Protocol (NTP). NTP is the protocol that is used to synchronize the clock on a network. It provides time within 100 milliseconds of the accurate time, but does not authenticate traffic.

The SNTP authentication page of the switch allows the administrator to configure NTP authentication keys to verify a time source. SNTP authentication should be used only in situations where strong authentication is not required as it does not provide the complex filtering mechanisms of NTP.

This document explains how to define SNTP Authentication through the Command Line Interface (CLI) of a switch. You may also configure SNTP authentication settings through the web-based utility of the switch. For instructions, click here.

Applicable Devices

- Sx300 Series

- Sx350 Series

- SG350X Series

- Sx500 Series

- Sx550X Series

Software Version

- 1.4.7.05 - Sx300, Sx500

- 2.2.8.04 - Sx350, SG350X, Sx550X

Configure SNMP Groups on a Switch

Step 1. Access the CLI of the switch.

Note: In this example, PuTTY is the application used to access the switch CLI. The default username and password is cisco/cisco. If you have customized your credentials, use your username and password.

Step 2. Switch to Global Configuration mode by entering the following command:

SG350X#configureterminal

Step 3. Define an SNTP Authentication Key using one of the following syntax:

SG350X(config)#sntp authentication-key [key-number] md5 [key-value]

SG350X(config)#encrypted sntp authentication-key [key-number] md5 [encrypted key-value]

Where:

- key-number - This specifies the number of the key. It can be from 1 to 4294967295.

- key-value - This specifies the value of the key. It can be from one to eight characters long.

- Encrypted-key-value - This specifies the key value in encrypted format.

SG350X(config)#sntp authentication-key 121110 md5 cisco

Note: In this example, sntp authentication-key 121110 md5 cisco is entered.

Step 4. Switch to Global Configuration mode by entering the following command:

SG350X(config)#exit

Step 5. (Optional) Enter the following command in Privileged EXEC mode to save the configuration.

SG350X#copy running-config startup-config

Step 6. (Optional) Press Y to save the settings in the startup configuration of the switch otherwise, press N to proceed without saving the configuration to the startup configuration of the switch.

Note: In this example, Y is pressed.

Step 7. Verify the sntp authentication key with the following command:

SG350X#show sntp configuration

Note: In this example, the MD5 Authentication keys are 121110 AR0EvVLMGAD24At8AbZCRXJgLKYwPRAx3qYDTZqk8Go=

You should now have configured an SNTP Authentication settings through the CLI of the switch.

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