H3C Technologies H3C S7500E Series Switches - Manual (Page 73)

3-9
A single device 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 client/server 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.
Configuring NTP Client/Server Mode
For devices working in the client/server mode, you only need to make configurations on the
clients, but not on the servers.
Follow these steps to configure an NTP client:
To do… Use the command… Remarks
Enter system view system-view —
Specify an NTP server for the
device
ntp-service unicast-server
[ vpn-instance
vpn-instance-name ]
{ ip-address | server-name }
[ authentication-keyid keyid |
priority | source-interface
interface-type interface-number
| version number ] *
Required
No NTP server is specified by
default.