How to Remove a Disk from Time Machine on Mac
All Mac users should have regular automatic backups setup with Time Machine, it’s easy to use and ensures that your personal data and entire Mac is recoverable in the event something goes wrong with the computer. Some people go even further and setup redundant Time Machine backups with multiple disks for added data protection. But sometimes you may decide a particular disk drive is no longer needed by Time Machine, and thus you’d like to remove that particular drive from the backup process without disabling all other Time Machine backups. This can be easily done, and all it does is stop backing up to the particular drive in question, it does not turn off Time Machine to other volumes, and it does not delete any of the backups on the removed drive.