IP Office Configuration:
This Section describes the IP Office configuration, with emphasis on the configuration specific to central voicemail.
Step 1) From a PC with the IP Office Manager installed, open the IP Office for configuration.
Double-click the System configuration tree item and select the LAN1 tab and note the IP Address.

IP Office System-LAN1
Step 2 ) Click the System tab and ensure that the License Server address is set to the IP Office IP Address of LAN1, since the needed license key is attached directly to the IP412 serial port. Alternatively, if the configuration uses a separate License Server PC, enter that PC’s address. Both configurations are supported. Click OK.
IP Office System-System Lab
In this case, you can use MM as a centralized VM.
Related document:
http://plecmovap03.avaya.com:9111/KNOVA_AKB/DocContent?DocID=003880119
OR
You can also use the above steps to assign the IPOffice the desired IP address per the customer network and then connect to it via the IPOffice manager