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5.1.3.
SNTP
The Network Time Protocol (NTP) is a protocol for synchronizing the clocks of
computer systems over packet-switched, variable-latency data networks. A less
complex implementation of NTP, using the same protocol but without requiring the
storage of state over extended periods of time is known as the
Simple Network Time
Protocol
(
SNTP
).NTP provides Coordinated Universal Time (UTC). No information
about time zones or daylight saving time is transmitted; this information is outside its
scope and must be obtained separately.
UDP Port: 123.
Daylight saving
is a period from late spring to early fall when many countries set their
clocks ahead of normal local time by one hour to give more daytime light in the evening.
Note:
1.
The SNTP server always replies the UTC current time.
2.
When the Switch receives the SNTP reply time, the Switch will adjust the time
with the time zone configuration and then configure the time to the Switch.
3.
If the time server’s IP address is not configured, the Switch will not send any
SNTP request packets.
4.
If no SNTP reply packets, the Switch will retry every 10 seconds forever.
5.
If the Switch has received SNTP reply, the Switch will re-get the time from NTP
server every 24 hours.
6.
If the time zone and time NTP server have been changed, the Switch will repeat
the query process.
7.
No default SNTP server.
5.1.3.1.
CLI Configuration
Node
Command
Description
enable
show time
This command displays current time
and time configurations.
enable
configure terminal
This command changes the node to
configure node.
configure time
HOUR:MINUTE:SECOND
Sets the current time on the Switch.
hour
: 0-23
min
: 0-59
sec
: 0-59
Note: If you configure Daylight
Saving Time after you configure the
time, the Switch will apply Daylight
Saving Time.
configure time date
YEAR/MONTH/DAY
Sets the current date on the Switch.
year
: 1970-
month
: 1-12