NOTE:
• In the ntp-service unicast-server command,
ip-address
must be a unicast address. It cannot be a
broadcast address, a multicast address or the IP address of the local clock.
• When the source interface for NTP messages is specified by the source-interface ar
ument, the source
IP address of the NTP messages is configured as the primary IP address of the specified interface.
• A device can act as a server to synchronize the clock of other devices only after its clock has been
synchronized. If the clock of a server has a stratum level hi
her than or equal to that of a client’s clock,
the client will not synchronize its clock to the server’s clock.
• You can configure multiple servers by repeating the ntp-service unicast-server command. The clients
will select the optimal reference source.
Configuring the NTP symmetric peers mode
For devices working in the symmetric mode, specify a symmetric-passive peer for a symmetric-active peer.
Following these steps to configure a symmetric-active device:
To do… Use the command… Remarks
Enter system view system-view —
Specify a symmetric-passive peer
for the device
ntp-service unicast-peer
{ ip-address | peer-name }
[ authentication-keyid keyid |
priority | source-interface
interface-type interface-number |
version number ] *
Required
No symmetric-passive peer is
specified by default.
NOTE:
• In symmetric mode, use any NTP configuration command in Configuring the operation modes of NTP
to enable NTP. Otherwise, a symmetric-passive peer will not process NTP messages from a
symmetric-active peer.
• In the ntp-service unicast-peer command,
ip-address
must be a unicast address, rather than a
broadcast address, a multicast address or the IP address of the local clock.
• When the source interface for NTP messages is specified by the source-interface ar
ument, the source
IP address of the NTP messages is configured as the primary IP address of the specified interface.
• Typically, at least one of the symmetric-active and symmetric-passive peers has been synchronized.
Otherwise, the clock synchronization will not proceed.
• You can configure multiple symmetric-passive peers by repeating the ntp-service unicast-peer
command.
Configuring NTP broadcast mode
The broadcast server periodically sends NTP broadcast messages to the broadcast address
255.255.255.255. After receiving the messages, the device working in NTP broadcast client mode
sends a reply and synchronizes its local clock.
For devices working in broadcast mode, configure both the server and the clients. NTP broadcast mode
can be configured only in the specific interface view, because an interface needs to be specified on the
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