New control units are supplied with no installed firmware or configuration. When first powered up, the control unit loads and installs the necessary firmware from the Avaya System SD card installed in the control unit. It then creates a default configuration matching the physical cards already installed in the control unit and any external expansion modules already attached to it.
You can perform a number of additional actions prior to installing the System SD card in order to pre-configure the system. These can greatly speed up the physical installation at the customer site as they can all be done in advance.