A Raspberry PI is a wonderful and powerful little computer. You can even run it as a server 24/7 all year round. There is just one snag: sooner or later the SD card gets corrupted during a write operation. Moving the root file system of your Raspberry PI to an external USB drive bypasses this problem. This article presents instructions on moving the root file system from the SD card to an external USB drive, such that you can boot your Raspberry PI with the root file system on the USB drive.