Can Time Machine Backup External Drives?
Yes, Time Machine can backup external drives. In fact, Time Machine can backup any drive that is connected to your Mac. This includes drives connected via USB, Thunderbolt, FireWire, or Ethernet.
One thing to note is that you cannot use an external drive as a Time Machine backup if the drive is encrypted. Time Machine will not be able to read the drive if it is encrypted.
If you have a lot of data …
