ntp update-calendar
Configure the FTOS to update the calendar (the hardware clock) with the NTP-derived time.
C-Series, E-Series, S-Series, Z-Series
Syntax
ntp update-calendar [minutes]
To return to default setting, use the no ntp update-calendar command.
Parameters
minutes
(OPTIONAL) Enter the number of minutes between updates from NTP 
to the hardware clock. The range is 1 to 1440. The default is 60 
minutes.
Defaults Not enabled.
Command Modes CONFIGURATION
Command History
Version 8.3.11.1 Introduced on the Z9000.
Version 7.6.1.0 Introduced on the S-Series.
Version 7.5.1.0 Introduced on the C-Series.
pre-Version 
6.1.1.0
Introduced on the E-Series.
show calendar
Display the current date and time based on the switch hardware clock.
C-Series, E-Series, S-Series, Z-Series, S4810
Syntax
show calendar
Command Modes
• EXEC
• EXEC Privilege
Command History
Version 8.3.11.1 Introduced on the Z9000.
Version 8.3.7.0 Introduced on the S4810.
Version 7.6.1.0 Introduced on the S-Series.
Version 7.5.1.0 Introduced on the C-Series.
pre-Version 
6.1.1.0
Introduced on the E-Series.
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