Time Machine volumes can’t be included in Time Machine backups

Time Machine in macOS can automatically back up every volume you have mounted on a Mac except those that you exclude. You manage the exclusions list by opening the Time Machine preference pane and clicking Options, where you can also add particular folder hierarchies, which appears as paths. (To exclude your Documents folder, for instance, you click the + sign and navigate to it to select the folder, but it appears in the list as ~/Documents, where the tilde means “your home directory.”) IDG

Time Machine can’t back up Time Machine volumes.To read this article in full, please click here