Step 1 From the Cisco Unified Communications Operating System Administration window, navigate to Settings>NTP Servers.
The NTP Server Settings window displays.
Step 2 You can add, delete, or modify an NTP server:
-To delete an NTP server, check the check box in front of the appropriate server and click Delete.
-To add an NTP server, click Add, enter the hostname or IP address, and then click Save.
-To modify an NTP server, click the IP address, modify the hostname or IP address, and then click Save.
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