一、apt更新源问题

　①备份旧更新源

mv /etc/apt/sources.list /etc/apt/sources.list.old

　②添加新更新源

cat > /etc/apt/sources.list << EOF
deb http://deb.debian.org/debian/ bullseye main contrib non-free
deb-src http://deb.debian.org/debian/ bullseye main contrib non-free

deb http://deb.debian.org/debian/ bullseye-updates main contrib non-free
deb-src http://deb.debian.org/debian/ bullseye-updates main contrib non-free

deb http://deb.debian.org/debian/ bullseye-backports main contrib non-free
deb-src http://deb.debian.org/debian/ bullseye-backports main contrib non-free

deb http://deb.debian.org/debian-security/ bullseye-security main contrib non-free
deb-src http://deb.debian.org/debian-security/ bullseye-security main contrib non-free
EOF

二、安装Docker

　①一键安装docker

 curl -sSL https://get.docker.com/ | sh

　②验证

docker --version

　③卸载docker

apt-get remove docker docker-engine
rm -fr /var/lib/docker/

三、debian11一键开启BBR加速

内容来自大幅度优化你的 VPS 网速

wget https://gist.githubusercontent.com/taurusxin/a9fc3ad039c44ab66fca0320045719b0/raw/3906efed227ee14fc5b4ac8eb4eea8855021ef19/optimize.sh && sudo bash optimize.sh