Configuring The Sntp Mode; Defining Sntp Authentication - Cisco SF500-24 Administration Manual

Administration: Time Settings
Configuring System Time
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STEP 3
STEP 4
Cisco 500 Series Stackable Managed Switch Administration Guide Release 1.3

Configuring the SNTP Mode

The device can be in active and/or passive mode (see
information).
To enable receiving SNTP packets from all servers on the subnet and/or to enable
transmitting time requests to SNTP servers:
Click Administration > Time Settings > SNTP Multicast/Anycast.
Select from the following options:
• SNTP IPv4 Multicast Client Mode (Client Broadcast Reception)—Select to
receive system time IPv4 Multicast transmissions from any SNTP server on
the subnet.
• SNTP IPv6 Multicast Client Mode (Client Broadcast Reception)—Select to
receive system time IPv6 Multicast transmissions from any SNTP server on
the subnet.
• SNTP IPv4 Anycast Client Mode (Client Broadcast Transmission)—Select to
transmit SNTP IPv4 synchronization packets requesting system time
information. The packets are transmitted to all SNTP servers on the subnet.
• SNTP IPv6 Anycast Client Mode (Client Broadcast Transmission)—Select to
transmit SNTP IPv6 synchronization packets requesting system time
information. The packets are transmitted to all SNTP servers on the subnet.
If the system is in Layer 3 system mode, click Add to enter the interface for SNTP
reception/transmission.
Select an interface and select the reception/transmission options.
Click Apply to save the settings to the Running Configuration file.

Defining SNTP Authentication

SNTP clients can authenticate responses by using HMAC-MD5. An SNTP server is
associated with a key, which is used as input together with the response itself to
the MD5 function; the result of the MD5 is also included in the response packet.
The SNTP Authentication page enables configuration of the authentication keys
that are used when communicating with an SNTP server that requires
authentication.
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SNTP Modes for more
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