Operation Manual – NTP
H3C S3100 Series Ethernet Switches
Chapter 1 NTP Configuration
1-9
Note:
z
In the symmetric peer mode, you need to execute the related NTP configuration
commands (refer to section
1.3
for details) to enable NTP on a symmetric-passive
peer; otherwise, the symmetric-passive peer will not process NTP messages from
the symmetric-active peer.
z
The remote device specified by
remote-ip
or
peer-name
serves as the peer of the
local Ethernet switch, and the local switch works in the symmetric-active mode. In
this case, the clock of the local switch and that of the remote device can be
synchronized to each other.
z
remote-ip
must not be a broadcast address, a multicast address or the IP address of
the local clock.
z
After you specify an interface for sending NTP messages through the
source-interface
keyword, the source IP address of the NTP message will be
configured as the IP address of the specified interface.
z
Typically, the clock of at least one of the symmetric-active and symmetric-passive
peers should be synchronized first; otherwise the clock synchronization will not
proceed.
z
You can configure multiple symmetric-passive peers for the local switch by
repeating the
ntp-service
unicast-peer
command. The clock of the peer with the
smallest stratum will be chosen to synchronize with the local clock of the switch.
1.3.3 Configuring NTP Broadcast Mode
For switches working in the broadcast mode, you need to configure both the server and
clients. The broadcast server periodically sends NTP broadcast messages to the
broadcast address 255.255.255.255. The switches working in the NTP broadcast client
mode will respond to the NTP messages, so as to start the clock synchronization.
An H3C S3100 series Ethernet switch can work as a broadcast server or a broadcast
client.
z
Refer to
Table 1-5
for configuring a switch to work in the NTP broadcast server
mode.
z
Refer to
Table 1-6
for configuring a switch to work in the NTP broadcast client
mode.
Note:
A broadcast server can synchronize broadcast clients only after its clock has been
synchronized.
