Upgrading WSL2 Debian 10 to 11

This a relatively easy upgrade, so it’s worth doing in situ if you’ve customized your distro. If you haven’t done anything you’d like to keep from your current installation, you can always download a fresh copy from the Microsoft Store.

First order of business is to open PowerShell and backup your current installation. Switch to the directory you’d like to hold your backup and execute:

wsl --export Debian debian10.tar

Next, launch your Debian terminal and do the usual update and upgrade:

sudo apt-get update && sudo apt-get upgrade

And then we’ll update the repositories by editing /etc/apt/sources.list. Modify the entries so they look like this. Mostly you’ll just be changing buster to bullseye, but there are other differences too. Edit carefully:

deb http://deb.debian.org/debian bullseye main
deb http://deb.debian.org/debian bullseye-updates main
deb http://security.debian.org/debian-security bullseye-security main
deb http://ftp.debian.org/debian bullseye-backports main

Another round of:

sudo apt-get update && sudo apt-get upgrade

Many packages will update, some will be held back. No worries, we’ll pick up the rest in a moment. Respond “Yes” if you’re asked about restarting services.

The last step is to do a “full-upgrade” which should pickup any packages that weren’t done before now, and also advance the version number from 10 to 11.

sudo apt full-upgrade

And that’s about it — enjoy Debian 11 “Bullseye”!