This article will show you how to upgrade Ubuntu 20.04 to 21.04 with command line. In order to upgrade your ubuntu to 21.04, you’ll need to upgrade to 20.10 first, and from there you can start upgrade your ubuntu to 21.04
Upgrade to Ubuntu 20.10
# Upgrade/update your current Ubuntu 20.04
sudo apt update
sudo apt upgrade
sudo apt dist-upgrade
# Remove all packages that no longer useful
sudo apt autoremove
Configure your release upgrade file
# Edit file /etc/update-manager/release-upgrades
sudo vi /etc/update-manager/release-upgrades
# Find and replace below variable
Prompt=normal
# Save and close
Perform upgrade ubuntu 20.10
# Type below command and follow instructions
sudo do-release-upgrade
Reboot your system once upgrade is done
Update your Ubuntu 20.10 to 21.04
Once your Ubuntu 20.04 is upgraded to 20.10, you can repeat the same step and run upgrade command to upgrade 20.10 to 21.04