Configuring the Unicast Client/Server Mode

In client/server mode, the clock on the client synchronizes with the master clock on the server.

Context

Commonly, specify the IP address of the NTP server on the client. The client and server can then exchange NTP packets using this IP address.

If the source interface that sends NTP packets is specified on the server, the IP address of the server configured on the client should be the same; otherwise, the client cannot process NTP packets sent from the server and clock synchronization fails.

Procedure

Configuring the NTP Client
Perform the following steps on the FW functioning as a client:
1. Access the system view.
```
system-view
```
2. Optional: Set the local source interface that receives NTP packets.
```
ntp-service [ ipv6 ] source-interface interface-type interface-number [ vpn-instance vpn-instance-name ]
```
  If source-interface is specified in both 2 and 3, use the source interface specified in 3 preferentially.
3. Set the NTP server with a specified IPv4 or IPv6 address.
  - ntp-service unicast-server ip-address [ version number | [ authentication-keyid key-id | autokey ] | source-interface interface-type interface-number | preference | vpn-instance vpn-instance-name | maxpoll max-number | minpoll min-number | burst | iburst | preempt | port port-number ] ^*
  - ntp-service unicast-server ipv6 ipv6-address [ [ authentication-keyid key-id | autokey ] | source-interface interface-type interface-number | preference | vpn-instance vpn-instance-name | maxpoll max-number | minpoll min-number | burst | iburst | preempt | port port-number ] ^*
  ip-address or ipv6-address is the address of the NTP server. It can be the IPv4 or IPv6 address of the host other than a broadcast address, a multicast address, or the IP address of the reference clock.
  
  When the unicast NTP server is specified, the local FW functions as the client automatically. The server needs to be configured with only a primary clock.
  
  For the unicast mode, after configuring the NTP client, you need to configure a security policy between the security zone where the source interface resides and Local zone to permit NTP packets. For the broadcast and multicast modes, you do not need to configure the security policy.
Optional: Configuring the NTP Server
Perform the following steps on the FW working as a server:
1. Access the system view.
```
system-view
```
2. Set the local source interface that sends NTP packets.
```
ntp-service [ ipv6 ] source-interface interface-type interface-number [ vpn-instance vpn-instance-name ]
```