It is already very common to use USB drives to install Linux distributions. You can test the system from them through Live sessions, you can install programs, save files and change various settings. But, as soon as you have to restart, all changes will be lost.
While this may be useful for different purposes, you may want to create a LiveUSB with persistent storage, which picks up the operating system right where you left off.
When you create a USB drive with persistent storage what you do is create a layer of up to 4 GB that works like some sort of virtual hard drive, roughly. Thanks to that layer any changes you make will remain in it, which means that every time you start the system from the USB will remain there.
This feature is ideal if you want to maintain a Linux system that you will use on different PCs. You will not have to leave everything to your liking every time you start the system every time you reboot, similar to what you would do to install and start Windows 10 from an external drive.
Now, it is worth clarifying that persistence of data is not necessary if you only plan to install an operating system, since after doing so you are supposed to run it from your hard drive.
The limitations of this system
That the LiveUSB has data persistence does not mean that you can do everything, it has its limitations. You will not be able to install important updates or hardware drivers. What you can do is install most existing software, which you can even upgrade.
Also keep in mind that it does not work on all distributions. For now we know that it works with Ubuntu, Fedora and distros based on them. The process for creating a LiveUSB with persistent storage is similar for all distributions that support it: download the appropriate ISO and follow the instructions we will give you below.
You will need a large enough USB drive first. Ubuntu, for example, needs at least 2GB of storage. If we add the 4 GB you need the persistence layer, you need a drive of at least 6 GB .
In this example we will create a LiveUSB with data persistence with a version of Ubuntu. From the distro headquarters they recommend using the Rufus tool to create the boot medium in Windows, but does not support the creation of USB drives with persistence. For this particular work we will have to use Linux Live USB Creator, also known as LiLi, which you can download. Install the program before continuing.
Now download the Ubuntu ISO that you want to place in the USB drive and insert the USB drive that you want to use in a port that you have free. Now open LiLi USB creator and choose the device in the first step.
The next step is to select the Ubuntu ISO. In the second step select the “ISO / IMG / ZIP” option.
The third part of the process is the one that interests us. Use the options you’ll find here to allocate the space you need for persistent storage. Move the slider you will see on the screen to choose the maximum amount of memory.
In the fourth step you can choose the options that you think apply before the creation of LiveUSB, while in the fifth step you can create the boot media properly by clicking on the button in the form of lightning.
The process will take its time, but it will display a message on the screen when finished. From there you can restart the computer to start a session from the unit. To verify that it works, log in from the USB and create a folder on the desktop. Then restart the computer and boot from the LiveUSB again. If the folder is still there, the process is completed successfully.