I use Time Machine, with an external hard drive connected by USB, to back up my MBA. If Time Machine is in the middle of backing up my drive and I close the lid of my computer, Time Machine will stop the backup and (as far as I can tell) will not resume backing up until I wake my computer back up.
Is there a way to change this behavior? I want it to continue backing up, until it finishes the backup, even when I close the lid of my computer in the middle of a backup. Is there a way to do that?