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New Member

CUCM 8.6 & VMware Workstation 8

Hello everyone

Is there any workaround for the following problem?

I've set up VM:

- 2 processors

- 250 Gb disk

- 4096 Mb DRAM

- type of operating system - RedHat Enterprise 4

The process of installation of CUCM stopped at the step of verification of NTP servers. Test has shown the NTP servers are accessible. But after I proceeded further, I got an error: "NTP-based clock correction failed, make sure your servers are accessible, port 123 is not blocked etc. etc."

Looks like VMware workstation doesn't allow to synchronize its hardware clock with NTP servers.



Everyone's tags (7)

CUCM 8.6 & VMware Workstation 8

I've installed CUCM under VMWare Fusion, so it's do-able.

I'd suggest making sure the VMs clock is the same as your NTP servers before starting the installer. That way, NTP shouldn't need to try to change the clock.


Please rate all helpful posts.

CUCM 8.6 & VMware Workstation 8


You need to specify external NTP server IP address. You cannot skip this step as it was in earlier version of CUCM. You can run NTP server on your windows box and point CUCM to windows IP address. ( in case you use host-only ). Or you can point to NTp servers on the internet in case of bridged/NAT interface used on the VM with CUCM.

NTP step should be covered in installation guide.


New Member

CUCM 8.6 & VMware Workstation 8


   I pointed my to my local ISR router and it worked fine. All CUCM builds will fail without NTP.

New Member

CUCM 8.6 & VMware Workstation 8

Same as rest - even though CUCM Publisher said NTP servers were fine, subscriber wouldn't accept. Finally had to put in NTP server of the 4510-e switch that VMWare/bare metal box was directly connected to and wait five minutes - then it went throgh without a hitch :-)