The 3-2-1 backup rule
  • 3 copies, 2 types of media, 1 copy off-site
  • Have 1 primary backup and 2 duplicates, in additional to the original data.
  • NAS, USB drive, Cloud storage, Server, Glacier, etc

For example, your laptop could be backed up to a NAS, a server, and glacier storage. Or 2 NAS and 1 archival cloud storage.