How to Upgrade Debian 10 to Debian 11

One of the advantages of the Debian operating system is easy to upgrade to the newer version.

Login to your Debian 10 server using SSH or console. Install all available software updates with the command

apt update && apt upgrade -y

Remove any unused packages

apt autoremove

Change /etc/apt/sources.list

Make a backup of the file

cp /etc/apt/sources.list ~/

Edit the file /etc/apt/sources.list

In the file, change all “buster” entries to “bullseye”. You can do this manually or using sed command

sed -i 's/buster/bullseye/g' /etc/apt/sources.list

Update System

Update repository cache with

apt update

Upgrade software with

apt upgrade

Do a full-upgrade with

apt full-upgrade

Now reboot system

reboot

After reboot, you need to make sure all services running properly, there is a chance some services won’t work as expected, in that case, you need to debug and fix i.

See Debian