Product and Software: This article applies to all Aruba MMS versions.
From the UI, it cannot be done.
From the Linux shell, do:
/opt/aruba/solid/solid.sh wipe /etc/init.d/mmgr start
On Windows MMS, open the command prompt and do:
cd "C:\Program Files\Aruba Mobility Management System\aruba\solid"
net start aruba-mms
Note that this does not overwrite things like the IP address of the server or other basic settings. It just shuts down the server and deletes the database.