How you run your file server is really up to you and how you intend to use it. Once they start it, most people never turn their file server off, running it 24/7 so every Mac on the network can access the server at any time. But you don’t have to run your Mac file server 24/7 if you don’t need ‘round-the-clock access. If you use your network for a home or small business, you may want to turn the file server off once you’ve finished work for the day. If it’s a home network, you may not want all family members to have late-night access. In both of these examples, creating a schedule that turns the server on and off at preset times might be a better approach than 24/7. This has the advantage of saving you a bit on your electric bill, as well as reducing heat buildup, which will save you on cooling loads if your home or office has air conditioning.
If you’re going to run your file server 24/7, you probably want to ensure that your Mac will restart automatically if there’s a power outage or your UPS runs out of battery time. Either way, 24/7 or not, you can use the ‘Energy Saver’ preferences pane to configure your server as needed.