Enabling SNTP in unicast mode (CLI)

Like broadcast mode, configuring SNTP for unicast mode enables SNTP. However, for unicast operation, you must also specify the IP address of at least one SNTP server. The switch allows up to three unicast servers. You can use the Menu interface or the CLI to configure one server or to replace an existing unicast server with another. To add a second or third server, you must use the CLI. For more on SNTP operation with multiple servers, see SNTP unicast time polling with multiple SNTP servers

Syntax:


timesync sntp

Selects SNTP as the time synchronization method.

Syntax:


sntp unicast

Configures the SNTP mode for unicast operation.

Syntax:


no sntp server priority < 1-3 > < ip-address > [version]

Use the no version of the command to disable SNTP.

priority: Specifies the order in which the configured SNTP servers are polled for the time.
ip-address: An IPv4 or IPv6 address of an SNTP server.
version: The protocol version of the SNTP server. Allowable values are 1 through 7; default is 3.

Syntax:


no sntp server priority <1-3> <ip-addr>

Deletes the specified SNTP server.

NOTE:

priority <1-3>

value must match what server is configured with. Deleting an SNTP server when only one is configured disables SNTP unicast operation.

Example:

To select SNTP and configure it with unicast mode and an SNTP server at 10.28.227.141 with the default server version (3) and default poll interval (720 seconds):

switch(config)# timesync sntp

Selects SNTP.

switch(config)# sntp unicast

Activates SNTP in unicast mode.

switch(config)# sntp server priority 1 10.28.227.141

Specifies the SNTP server and accepts the current SNTP server version (default: 3).

Configuring SNTP for unicast operation

switch(config)# show sntp

 SNTP Configuration

  Time Sync Mode: Sntp
  SNTP Mode : Unicast
  Poll Interval (sec) [720] : 720


  Priority SNTP Server Address                            Protocol Version
  -------- ---------------------------------------------- ----------------
  1        2001:db8::215:60ff:fe79:8980 7
  2        10.255.5.24 3
  3        fe80::123%vlan10 3

In this Example:, the Poll Interval and the Protocol Version appear at their default settings.

Both IPv4 and IPv6 addresses are displayed.

Note: Protocol Version appears only when there is an IP address configured for an SNTP server.

If the SNTP server you specify uses SNTP v4 or later, use the sntp server command to specify the correct version number. For example, suppose you learned that SNTP v4 was in use on the server you specified above (IP address 10.28.227.141). You would use the following commands to delete the server IP address , re-enter it with the correct version number for that server.

Specifying the SNTP protocol version number

switch(config)# no sntp server 10.28.227.141 ¹
switch(config)# sntp server 10.28.227.141 4 ²
switch(config)# show sntp
 
 SNTP Configuration

  Time Sync Mode: Sntp
  SNTP Mode : Broadcast
  Poll Interval (sec) [720] : 600

  IP Address     Protocol Version
  -------------  -----------------
  10.28.227.141  4 ³

¹Deletes unicast SNTP server entry.
²Re-enters the unicast server with a non-default protocol version.
³show sntpdisplays the result.