Use this command to configure the NTP server to allow the system clock to be synchronized by a time server. You can configure multiple NTP servers. The server selection algorithm picks the server for time synchronization. Configuring a preferred status overrides the algorithm, and the configured server is used for time synchronization. Configuring a preferred server reduces switching back and forth among servers.
Preferred status indicates whether this NTP server is the preferred server if two servers show different times. This argument is meaningful only when you configure two servers; if you configure three or more, the NTP function automatically finds the most reliable server.
| Default | None |
| Format | ntp server <server-address> [version <number>] [key <key-id>] [minpoll <interval>] [maxpoll <interval>] [prefer] [burst] [iburst] |
| Mode | Global Config |
| Parameter | Description |
|---|---|
| server-address | Server address (IPv4 or IPv6) or hostname of the server, for this client to synchronize time. The hostname range is 1 to 256 characters. |
| version <number> | The protocol version. The default is 4. The range is 1 to 4. |
| key <key-id> | Authentication key. The key ID range is 1 to 4,294,967,295. |
| minpoll <interval> | Minimum polling interval in seconds as a power of 2. The range is 4 to 17, which in seconds is 16 to 131,072. The default is 64 seconds. |
| maxpoll <interval> | Maximum polling interval in seconds as a power of 2. The range is 4 to 17, which in seconds is 16 to 131,072. The default is 1024 seconds. |
| prefer | Preference status for this server. A value of true indicates this server is preferred in server selection. |
| burst | Sends a series of packets instead of a single packet within each synchronization interval to achieve faster synchronization. |
| iburst | Same as burst, but applicable during initial synchronization. |
Example: The following is an example of the command.
(Routing) #configure (Routing) (Config) #ntp server 1.1.1.1
