Backing up your data on a regular basis is essential so that if you happen to lose them, you easily recover them.Follow the below steps that how to recover data from mac os not booting.
Step 1
Establish a connection between your external hard drive and the Mac computer.
Check if the connected external hard drive has adequate storage space to save the backup files.
Step 2
Shut Down the Mac computer.
Turn on the Mac computer and press the Command and R keys at the same time.
Hold both the keys until the Apple logo appears on the computer screen.
Wait until the OS X Utilities window opens. After choosing the Disk Utility option, click the Continue button.
The Disk Utility dialog window will display on the screen. Select the disk that you need to back up.
On the desktop of the Mac computer, click the File tab and select the New Image option.
Choose the ‘Image from X’ option. Note: The letter X denotes the name of your disk.
If needed, change the name in the Save As field. Choose the external drive name from the Where drop-down menu.
Select the Compressed option from the Format drop-down list. Click the Save button in the Disk Utility dialog window.
This process might take more time. Wait patiently until the backup files are stored on the external hard drive.
By using these steps that we can execute that how to recover data from mac os not booting.