Take a Snapshot with USB Drive

Another handy technique is to copy your home directory to a USB thumb drive or external drive:

• Select a USB drive. Use a drive with a capacity large enough to accommodate your data (128-1024 GB). For the most rapid snapshot, use a USB 3.0 or later drive that has fast transfer rates. We use the SanDisk Extreme Pro, which offers capacities up to 1TB and transfer speeds up to 420/380 MB/s read/write. The 512 GB capacity drive cost less than $100 as of 2021-08-21. Smaller drives with good write speeds can cost far less, but be careful: many USB drives have write speeds that are much slower than their advertised read speeds.
• Open the Dolphin file manager. It will show a panel on the left and a file area on the right.
• Click on the path above the file area and select /home. You should now see all user home directories on your system.
• Click on the Split icon at the top right to split the file area in two. Click on an empty space in the right-hand file area to make it active.
• Insert a formatted USB drive. Within 5 seconds, a USB drive name should appear on the bottom left side of the Dolphin window, under Devices. Click on this name to show the contents of this drive in the right-hand file area.
• Copy the desired folders from the /home directory to the USB drive by dragging them from the left-hand file-area to the right-hand file area. When prompted, select copy. Do NOT move the directories as this could harm your system!.
• Once all files are copied, the backup is complete. On the bottom left side of the Dolphin window, under Devices, right-click on the USB drive name to show a contextual menu. Click on Safely Remove and then remove the physical drive after confirmation by the Device Notifier in the system tray.

Because of file permissions, you may not be able to copy all files. When using Dolphin on 22.04, you can right-click on a folder and Open as Administrator to copy additional files. On 20.04, one can add the Open as Root service to Dolphin, but use this cautiously: click on [Hamburger Menu] > Configure Dolphin… > Context Menu (or Services) > Download New Services…. Then search for and install "Open Dolphin As Root". After installation, you can right-click on a folder or file and select Actions > Open as Root to access it as root.

Backup for Clean Install

If you decide to clean install the OS, we have found it very useful to backup the following data to a completely separate disk directory before proceeding:

• A screenshot, desktop-screenshot.png of your desktop. Use spectacle to create this.
• A directory that is a copy of your home directory.
• A file, etc.tgz, which contains all the files from the /etc directory. To create, run sudo tar cvzf etc.tgz /etc in the backup directory.
• A file, apps-to-reinstall.txt, where you list all the apps you know you want to install again. We recommend you look through the app menu for guidance and use kate or other editor to enter your picks into this file.
• A file, installed-packages.txt, that lists all installed packages. To create, run apt list --installed > installed-packages.txt

After the clean install, we recommend the following steps to restore your data:

• Review desktop-screenshot.png to help restore your desktop.
• Copy the home directory data data to the freshly formatted disk. You can inspect and merge configurations from the old home directory. For example, meld home-backup/.config ~/.config or meld home-backup/.ssh ~/.ssh.
• Unpack etc.tgz file and compare it to the new /etc directory.
• Use apps-to-reinstall.txt and installed-packages.txt to the software you wish to install. We recommend installing apps from Curated Apps when available, as this will set up the correct repositories and keys in almost all cases.

Other Solutions

Cloud storage, such as Dropbox, Microsoft OneDrive, or Google Drive, can often provide multiple versions of files using heuristics. However, we recommend explicitly versioned backups such as those provided by SCMSs (Source Control Management Systems like Git) for more exact control. Ultimately, one must balance convenience and storage requirements with completeness. And remember, any backup solution is better than none.

Disclaimer

We try hard to provide a useful solution validated by professionals. However, we cannot anticipate every situation, and therefore cannot guarantee this procedure will work for your needs. Always backup your data and test the solution to determine the correct procedure for you.

THIS SOLUTION IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOLUTION, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.