apt-get update
apt-get upgrade
apt-get dist-upgrade
Upgrade from Debian Jessie 8 to Debian 9
nano /etc/apt/sources.list
deb http://httpredir.debian.org/debian stretch main contrib non-free
deb http://httpredir.debian.org/debian stretch-updates main contrib non-free
deb http://security.debian.org stretch/updates main contrib non-free
apt-get update
apt-get upgrade
apt-get dist-upgrade
cat /etc/os-release
apt-get autoremove
debian 9升级到debian 10
apt-get update && apt-get upgrade
sed -i 's/stretch/buster/g' /etc/apt/sources.list
apt-get update && apt-get upgrade
apt-get dist-upgrade
reboot
lsb_release -a