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Mac Basics: Time Machine backs up your Mac
If you have an AirPort Time Capsule on your home network, you can use it as your Time Machine backup device. See the documentation that came with your AirPort Time Capsule for information about setting it up on your home network. Once your AirPort Time Capsule has been configured for your home network:
- Open Time Machine preferences and click "Select Disk…".
- From the sheet that appears, select the AirPort Time Capsule you would like to use for backup.
In OS X Mountain Lion or later you can select the "Encrypt backups" option to encrypt the backup on the AirPort Time Capsule using FileVault 2.
Tip: Click "Set up Other Time Capsule" to open AirPort utility to setup and configure your AirPort Time Capsule. Enter the name and password or password only that you set for your AirPort Time Capsule via the Airport Utility.
About the first backup to an AirPort Time CapsuleYour initial backup may be faster if you leave your computer in the same room as the AirPort Time Capsule, or use an Ethernet cable to connect your Mac to one of the Ethernet ports on the AirPort Time Capsule. You should not interrupt the initial backup connection by sleeping or shutting down the computer. You can continue to use your Mac while Time Machine backs up. Additional information is available about backing up with an AirPort Time Capsule for the first time.
Once the initial backup is completed, Time Machine performs subsequent backups of only the files that have changed on your Mac since the last backup was performed. Subsequent backups happen when a connection between the Mac and the backup drive is available. You can manually initiate a Time Machine backup cycle by selecting "Back up Now" from the Time Machine menu in the menu bar.
Best of luck,