How to configure Cisco router as NTP server
1- you have to obtain public NTP server addresses from www.ntp.org
2- configure you router with NTP server IP
GK_RTR#configure terminal
GK_RTR(config)#ntp server 64.209.210.20
GK_RTR(config)#ntp source lo
GK_RTR(config)# ntp master
GK_RTR(config)#clock timezone ARIZONA -7
3- Verifying NTP Configurations
GK_RTR#show ntp associations
GK_RTR#show clock
4- After you configure the Cisco router to synchronize with an NTP server, you can configure it to provide date and time information to a CUCM server and other devices,
Note :- If you want to allow your Router act as NTP server and specify specific interface to provide NTP services then you have to give command “ntp source ” before “ntp master” otherwise it will give NTP services from 127.0.0.1 .
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