Defining Sntp Authentication - Cisco SF500-24 Administration Manual

System Time
Configuring System Time
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Cisco 500 Series Stackable Managed Switch Administration Guide
Configuring the SNTP Mode
The switch 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. The
Multicast/Anycast
page opens.
Select from the following options:
• SNTP Multicast Client Mode (Client Broadcast Reception)—Select to
receive system time from any SNTP server on the subnet.
• SNTP Anycast Client Mode (Client Broadcast Transmission)—Select to
transmit SNTP Broadcast synchronization packets requesting system time
information. If SNTP servers have been defined, the packets go to these
servers; otherwise, the packets are transmitted to all SNTP servers on the
subnet.
If the system is in Layer 3 (router) mode (the 500X device is always in Layer 3
mode), click Add to enter the interface for SNTP reception/transmission. The Add
SNTP Interface Settings page opens.
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.
The authentication key is created on the SNTP server in a separate process that
depends on the type of SNTP server you are using. Consult with the SNTP server
system administrator for more detail on this.
SNTP Modes for more
SNTP
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