UMN:CLI
User Manual
V8102
78
To display a configured NTP, use the following command.
Command
Mode
Description
show ntp
Enable
Global
Shows a configured NTP function.
To synchronize the system clock, the system periodically sends the NTP message to the
NTP server. You can configure the system to bind the IP address to the message which
allows the NTP server to recognize your system.
To bind the IP address to the NTP message, use the following command.
Command
Mode
Description
ntp bind-address
A.B.C.D
Global
Specifies the IP address to be bound to the NTP mes-
sage.
no ntp bind-address
Deletes a specified IP address.
To specify the polling interval for the time synchronization with the NTP server, use the
following command.
Command
Mode
Description
ntp poll-interval
<6-17>
Global
Sets the NTP polling interval.
(default: 16 (2^16=65535, 18Hour))
no ntp poll-interval
Deletes the configured NTP polling interval.
4.1.5.5
Simple Network Time Protocol (SNTP)
NTP (Network Time Protocol) and SNTP (Simple Network Time Protocol) are the same
TCP/IP protocol in that they use the same UDP time packet from the Ethernet Time Serv-
er message to compute accurate time. The basic difference in the two protocols is the al-
gorithms being used by the client in the client/server relationship.
The NTP algorithm is much more complicated than the SNTP algorithm. NTP normally
uses multiple time servers to verify the time and then controls the rate of adjustment or
slew rate of the PC which provides a very high degree of accuracy. The algorithm deter-
mines if the values are accurate by identifying time server that doesn’t agree with other
time servers. It then speeds up or slows down the PC's drift rate so that the PC's time is
always correct and there won't be any subsequent time jumps after the initial correction.
Unlike NTP, SNTP usually uses just one Ethernet Time Server to calculate the time and
then it "jumps" the system time to the calculated time. However, it can have back-up
Ethernet Time Servers in case one is not available.
To configure the switch in SNTP, use the following commands.
Command
Mode
Description
sntp SERVER1
[
SERVER2
]
[
SERVER3
]
Global
Enables SNTP function with a specified SNTP server.
SERVER: server IP address (maximum 3 servers)