press the power button at the left side of the server’s front panel to turn it on.

the power indicator light turns on, and the server starts up. status lights on the front panel indicate network connection, system activity, and drive module use.
detailed instructions for setting up all the services and options of the mac os x server softwae are provided in the software documentation included with the server. see the quick start for xserve booklet for a roadmap to the software documentation.