In this lesson for macOS Mojave, I look at how to set up Time Machine to back up your Mac. With Time Machine, as long as you have an external hard drive configured for Time Machine, your computer will back up any new files or changed files every hour. You can also set up two or more hard drives to be used as Time Machine for extra protection.
Setting Up Time Machine on your External Drive
When you plug in an external drive to your Mac, in most cases it will ask you if you want to use it as a Time Machine backup. If you say yes, your computer will start using that hard drive for its backup. You can also configure a hard drive manually by going to Time Machine in System Preferences. Once the Time Machine preference pane opens, click on Select Disk. A sheet will drop down where you can see all your hard disks being used for Time Machine and available disks for Time Machine. Select the disk you want to use from Available Disks, and then click Use Disk. After that, the hard drive will be used for backing up your Mac. To Remove a disk, select it from Backup Disks, and then click on Remove Disk.
What Time Machine Backs Up
As long as your hard drive is connected to your Mac, Time Machine will backup any changes every hour. After that, it keeps the hourly backups for 24 hours. After that, it keeps daily backups for the past month. Then it keeps the weekly backup for all previous months. It will eventually delete the backup, your oldest backups, when the disk becomes full, so you do not want to use Time Machine for an archive.
Show Time Machine in Menu Bar
This will show Time Machine as a menu extra in the Menu Bar. I recommend turning this on as then you can see when your computer was last backup up and force a backup. To do this, just click on the Time Machine icon in the Menu Bar after you turn this on.
Time Machine Options
When you click on Options, you can add folders and external drives that you want to exclude from being backed up. Just drag the folder or external drive to the sheet that drops down. You can also click on the ‘+’ to add folders and external drives. To remove a folder or external drive from the exclude list, select it in the list and click on ‘-‘. You can also set if you want to be notified after old backups are deleted.
See this Lesson Action
To see this lesson in action, take a look at the video above.