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The following describes how an association is established in different association modes:
•
Client/server
mode
—After you specify an NTP server, the system creates a static association
on the client. The server simply responds passively upon the receipt of a message, rather than
creating an association (static or dynamic).
•
Symmetric active/passive mode
—After you specify a symmetric-passive peer on a
symmetric active peer, static associations are created on the symmetric-active peer, and
dynamic associations are created on the symmetric-passive peer.
•
Broadcast or multicast mode
—Static associations are created on the server, and dynamic
associations are created on the client.
A single device can have a maximum of 128 concurrent associations, including static associations
and dynamic associations.
Perform this task to restrict the number of dynamic associations to prevent dynamic associations
from occupying too many system resources.
To configure the maximum number of dynamic associations:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Configure the maximum
number of dynamic sessions
allowed to be established.
ntp-service
max-dynamic-sessions number
By default, the command can
establish up to 100 dynamic
sessions.
Setting a DSCP value for NTP packets
The DSCP value determines the sending precedence of a packet.
To configure a DSCP value for NTP packets:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Set a DSCP value for NTP
packets.
•
IPv4
packets:
ntp-service dscp
dscp-value
•
IPv6
packets:
ntp-service ipv6 dscp
dscp-value
The default DSCP value is 48 for
IPv4 packets and 56 for IPv6
packets.
Configuring the local clock as a reference source
Follow these guidelines when you configure the local clock as a reference source:
•
Make sure the local clock can provide the time accuracy required for the network. After you
configure the local clock as a reference source, the local clock is synchronized, and can operate
as a time server to synchronize other devices in the network. If the local clock is incorrect,
timing errors occur.
•
Before you configure this feature, adjust the local system time to make sure it is accurate.
To configure the local clock as a reference source:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
