
Operation Manual – NTP
H3C S5500-EI Series Ethernet Switches
Chapter 1 NTP Configuration
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1.2 NTP Configuration Task list
Complete the following tasks to configure NTP:
Task
Remarks
Configuring the Operation Modes of NTP
Required
Configuring Optional Parameters of NTP
Optional
Configuring Access-Control Rights
Optional
Configuring NTP Authentication
Optional
1.3 Configuring the Operation Modes of NTP
Switches can implement clock synchronization in one of the following modes:
z
Server/client mode
z
Symmetric mode
z
Broadcast mode
z
Multicast mode
For the server/client mode or symmetric mode, you need to configure only clients or
symmetric-active peers; for the broadcast or multicast mode, you need to configure
both servers and clients.
Note:
A single switch can have a maximum of 128 associations at the same time, including
static associations and dynamic associations. A static association refers to an
association that a user has manually created by using an NTP command, while a
dynamic association is a temporary association created by the system during operation.
A dynamic association will be removed if the system fails to receive messages from it
over a specific long time. In the server/client mode, for example, when you carry out a
command to synchronize the time to a server, the system will create a static association,
and the server will just respond passively upon the receipt of a message, rather than
creating an association (static or dynamic). In the symmetric mode, static associations
will be created at the symmetric-active peer side, and dynamic associations will be
created at the symmetric-passive peer side; In the broadcast or multicast mode, static
associations will be created at the server side, and dynamic associations will be
created at the client side.