How to partition a block device with GParted
The tool GParted is able to shrink partions and keep the data, provided that they fit in the new partition. Attention: this is risky, because if it fails while the operation is not completed, the data will be lost. Therefore, make sure to have a backup before shrinking a partition with data.
To start GParted, select the Application Menu on the top left.
Enter the first characters of the name of the application until it appears. Select the application.
Executing GParted requires root (sudo) rights.
Enter the user password and click on “Authenticate”.Gparted will start.
On the top right in the Gparted window, select the desired disk, here /
With a right mouse click, select Resize/Move.
Here you can resize the partition and keep the data.
Check for more Linux related articles.