We had the same question. We are wanting to change the subnet from 10 to 11 and are planning on doing it over the Christmas break. We asked our Cisco sales engineer and he didn't think it would be any problem. I'll let you know how it goes in a couple of weeks.
Yes, you can. Theres no problem with that. But you have to consider the following. If you use DNS you have to update your DNS server in order to register the changes you make. And if you change your call manager Hostname to IP Address you need to change it manually. Then if you also modify some parameters on the Call Manager service parameters (using IP address of the call manager instead of using the hostname) you need to change it also. In short you must change all parameters that are using IP Address of your call manager.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.