2 Ways to Upgrade Ubuntu 20.04/21.04 To 21.10 (GUI & Terminal)
Ubuntu 21.10, codenamed Impish Indri, is released on October 14, 2021. This tutorial is going to show you 2 ways to upgrade Ubuntu 20.04/Ubuntu 21.04 to 21.10. The first method uses the graphical update manager and the second method uses command line. Usually, you use the graphical update manager to upgrade Ubuntu desktop and use the command line to upgrade Ubuntu server, but the command-line method works for desktops too.
Ubuntu 20.04 is a long-term support (LTS) release, which will be supported for 5 years. Ubuntu 21.10 is a non-LTS release, which means it will be supported for 9 months only, until July 2022. If you prefer stability over bleeding edge, then stick with Ubuntu 20.04. But if you want to experience latest and greatest software, you can follow this tutorial to upgrade from Ubuntu 20.04 to 21.10.
Ubuntu 21.04 will reach end of life in January next year, so I recommend 21.04 users upgrade to Ubuntu 21.10 ASAP.
Hint: Before doing the upgrade, you can use the systemback program to create a bootable ISO image from your current OS. If the upgrade fails, you can easily restore your OS with the bootable ISO. Everything on your OS including software and files will be intact. If you are using a laptop, please connect your power source.
Read full tutorial here: https://www.linuxbabe.com/ubuntu/upgrade-ubuntu-20-04-21-04-to-21-10