54
NTP Configuration
Wh n configuring NTP, go to these
e
sections for information you are interested in:
z
Introduction to NTP
z
NTP Configuration Task List
z
Configuring NTP Implementation Modes
z
Configuring Access Control Right
z
Configuring NTP Authentication
Parameters
z
Configuring Optional NTP
Displaying NTP Configuration
z
es
z
Configuration Exampl
Intro
a time synchronization protocol defined in RFC 1305. It is used for time
devices that have clocks in a network so that the
duction to NTP
Network Time Protocol (NTP) is
synchronization between a set of distributed time servers and clients. Carried over UDP, NTP transmits
packets through UDP port 123.
NTP is intended for time synchronization between all
clocks of all devices can keep consistent. Thus, the devices can provide multiple unified-time-based
applications (see section
Applications of NTP
).
A local system running NTP can not only be synchronized by other clock sources, but also serve as a
clock source to synchronize other clocks. Besides, it can synchronize, or be synchronized by other
ing NTP messages.
Appli
racy, it is unfeasible for an administrator to perform the operation. However, an
erforming
NTP
NTP
z
sis of the log information and debugging information collected
hat generate the
z
that the clocks of all network devices be consistent.
ecution order.
operations between a backup server and a host, you must make
NTP
following advantages:
systems by exchang
cations of NTP
As setting the system time manually in a network with many devices leads to a lot of workload and
cannot ensure accu
administrator can synchronize the clocks of devices in a network with required accuracy by p
configuration.
is mainly applied to synchronizing the clocks of all devices in a network. For example:
In network management, the analy
from different devices is meaningful and valid only when network devices t
information adopts the same time.
The billing system requires
z
Some functions, such as restarting all network devices in a network simultaneously require that
they adopt the same time.
z
When multiple systems cooperate to handle a rather complex transaction, they must adopt the
same time to ensure a correct ex
z
To perform incremental backup
sure they adopt the same time.
has the
54-1
