Backup entire multisite or only individually?

Just installed snapshot and ran one. But, it only backed up the primary site.

Do I need to select each site and back them up manually? Is there a way to backup the entire multisite with one job?

I've got 4 sites, so it's not the end of the world if I have to run each job separately, but it would save some time if I could run just one job.

Thanks,
Craig