If you use Windows Server Backup then chances are you have the scheduled task that starts the backup still using the default settings that was created. For the most part this is fine.
However, recent experiences have led me to make one small change. If you have a server crash for whatever reason, the default setting for the backup task is to run the backup if the previous event was missed. This means that if the crash happened before teh backup time, then when you bring the server back up it will attempt to start the backup right away.
This can be a real pain as you may be in the process of trying to get services running again and the disk (and system) will run painfully slow while the backup tries to run. You also probably don’t really want a backup done just yet until you know you have a system in a good state that you actually want backed up. All depends on your circumstances.