HCIE NTP mode—broadcast mode
The broadcast mode of NTP is generally suitable for high-speed networks with multiple workstations that do not require high accuracy. The so-called broadcast mode, a typical example is that there are one or more NTP servers in the network, which send broadcast messages to the workstations.
In broadcast mode, the broadcast server periodically sends NTP messages to the restricted broadcast address 255.255.255.255, where the Mode field of the message is 5, which means broadcast mode or multicast mode. A host running in broadcast mode usually provides synchronization information to all peers, but does not modify its own clock.
In broadcast mode, the client listens to clock synchronization messages from the server. When the first NTP message is received, the client and server exchange NTP messages with the Mode field of 3 (client mode) and 4 (server mode). The client first enables a short server/client mode to exchange messages with the remote server to obtain the network delay between the client and the server. After that, the broadcast mode is restored, and the clock synchronization message is continued to be monitored, and the local clock is synchronized again according to the incoming clock synchronization message.
The broadcast mode is required to be in the same LAN during configuration, and the client can be synchronized only when the server-side clock is synchronized.
The server configuration is as follows:
A. Use the command interface interface-type interface-number to specify the interface for sending NTP broadcast messages
And enter the interface view.
B. For the Ethernet interface, the configuration under the interface only takes effect on the Layer 3 interface, and the Layer 2 interface does not take effect.
C. Use the command ntp broadcast-server [version number | authentication-keyid key-id |
port port-number] *, configure the local switch module as an NTP broadcast server.
If you specify the authentication-keyid parameter, please configure NTP authentication first.
D. If you specify the port parameter, you also need to use the ntp port port-value command on the broadcast client to configure and service
The same port number on the server side.
Configure the following on the client:
A. Use the command interface interface-type interface-number to specify the interface for sending NTP broadcast messages
And enter the interface view.
B. For the Ethernet interface, the configuration under the interface only takes effect on the Layer 3 interface, and the Layer 2 interface does not take effect.
C. Use the command ntp broadcast-client to configure the local switching module as an NTP broadcast client
