回帖：deb https://mirrors.tuna.tsinghua.edu.cn/armbian buster main utils
deb-src https://mirrors.tuna.tsinghua.edu.cn/armbian buster main utils
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ buster main non-free contrib
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ buster-updates main non-free contrib
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ buster-backports main non-free contrib
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ buster main non-free contrib
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ buster-updates main non-free contrib
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ buster-backports main non-free contrib
deb http://security.debian.org/ buster/updates main
deb-src http://security.debian.org/ buster/updates main

sudo gpg --keyserver keyserver.ubuntu.com --recv-keys 93D6889F9F0E78D5
sudo gpg --export --armor 93D6889F9F0E78D5 | sudo apt-key add -

sudo apt-get update

root@armbian:~# curl 'https://keyserver.ubuntu.com/pks/lookup?op=get&search=0xdf00faf1c577104b50bf1d0093d6889f9f0e78d5' |gpg --dearmor| sudo tee /etc/apt/trusted.gpg.d/armbian.gpg
cp -a /etc/apt/trusted.gpg.d/armbian.gpg /usr/share/keyrings/
https://blog.csdn.net/koral_yui/article/details/144944194