How to Upgrade Linux Mint 20.3 to Linux Mint 21
If you do not wish to do a fresh Linux Mint 21 Vanessa installation, you can simply upgrade from an earlier version…
Before you proceed, note that this is a major upgrade and it is bound to take several hours. * Besides, after initiating the upgrade process, the upgrade tool will require your current Linux Mint installation to be up to date (you will have to install updates where necessary) and to prepare system snapshots as well.
So, do not rush, kindly do not take shortcuts that may negatively affect the whole upgrade process…
Step 1: Install mintupgrade Tool
First, open a terminal, run the following commands to refresh your apt-cache, and install the mintupgrade upgrade tool:
$ sudo apt update
$ sudo apt install mintupgrade…
https://community.linuxmint.com/tutorial/view/2
* Several hours to upgrade OS ? in 2022 ? (does the process use only 1/2 Core of CPU and 640K of RAM ?)