You can upgrade to Ubuntu 20.04.1 LTS from either Ubuntu 18.04 LTS or Ubuntu 19.10.Ensure that you have all updates installed for your current version of Ubuntu before you upgrade.Confirm that you also have a network connectivity to one of the official mirrors or to a locally accessible mirror as there are no offline upgrade options.
Procedure to Follow
- Install update-manager-core if it is not already installed.
- Make sure the Prompt line in /etc/update-manager/release-upgrades is set to ‘normal' if you are using 19.10, or ‘lts' if you are using 18.04 LTS.
- Launch the upgrade tool with the command sudo do-release-upgrade on 19.10; use sudo do-release-upgrade -d if you are using 18.04 LTS.
- Follow the on-screen instructions.
Note that the server upgrade will use GNU screen and automatically re-attach in case of dropped connection problems.
The -d switch is necessary to upgrade from Ubuntu 18.04 LTS as upgrades have not yet been enabled and will only be enabled after the first point release of 20.04 LTS.