Yamaha#configure terminal
Yamaha(config)#clock timezone +9:00 (1)
Yamaha(config)#ntpdate server ipv4 192.168.1.1 (2)
Yamaha(config)#ntpdate server name ntp.nict.jp (3)
Yamaha(config)#ntpdate interval 24 (4)
Yamaha(config)#exit
Yamaha#show clock (5)
10:03:20 GMT+9:00 Wed Oct 10 2018
Yamaha#show ntpdate (6)
NTP server 1 : 192.168.1.1
NTP server 2 : ntp.nict.jp
adjust time : Wed Oct 10 11:46:30 2018 + interval 24 hour
sync server : 192.168.1.1