NTP Call Manager

[acastilloh5690]

Hello, I have a Cisco Call Manager, with NTP configured, but there is a 3 minute difference between the time displayed on the IP phones, compared with the time of the servers. What can be the cause of it?

[Vaijanath Sonvane]

Hi,

Are you having this issue for all IP Phones or for few Phone? Do you have separate Phone NTP reference configured for IP Phones or are you using CUCM Server time? Is the time on all CUCM Servers synchronized with NTP Servers? You can check NTP status under CUCM OS administration using CLI command "utils ntp status". Make sure that NTP stratum level is less than 4 on publisher for optimal performance. If NTP time is synchronized on all servers and if the time is correct, then try upgrading the firmware on few phones and see the status.