NTP / CUCM 12.5 Installation

[mid230]

I am installing CUCM 12.5 in a lab environment where I connect my laptop directly to the server via a switch. The CUCM will not be connected to the network. I will not add DNS IP.

Will the installation compete successfully even though the CUCM will not be able to confirm the NTP IP address as it is not connected to the network.

[Jaime Valencia · Accepted solution]

No, an NTP is mandatory during the installation. After you enter the NTP server(s) they're checked right after that step to confirm they're valid and will not allow you to move if none are valid.

[mid230]

Can I use my laptop Windows as the NTP server to complete the installation?

[Jaime Valencia]

Windows NTPs are not supported, you can review NTP requirements in the SRND.

[mid230]

Thanks

[Nithin Eluvathingal]

you can make your cisco switch  a ntp server. if you have are using a cisco switch to connect the server try the below commands. 

 ntp master 2

 ntp server time.google.com>> switch sync time from time.google.com.internet access is required for switch.

[Roger Kallberg]

For a lab you can if you want skip the connection to an external NTP server and just use the internal clock in the switch as the time for the NTP.

We did this for an isolated network that we stood up for a migration process from 5 down to 3 UC (CM, CUC, CUPS and CCX) systems that we did a few years back. For the purpose of this it worked perfectly.