一、备份原有配置：
cp /etc/apt/sources.list /etc/apt/sources.list.bak
二、配置
# 阿里镜像源 deb https://mirrors.aliyun.com/debian bullseye main non-free contrib deb https://mirrors.aliyun.com/debian bullseye-updates main non-free contrib deb https://mirrors.aliyun.com/debian bullseye-proposed-updates main non-free contrib deb https://mirrors.aliyun.com/debian bullseye-backports main non-free contrib deb https://mirrors.aliyun.com/debian bullseye-backports-sloppy main non-free contrib deb-src https://mirrors.aliyun.com/debian bullseye main non-free contrib deb-src https://mirrors.aliyun.com/debian bullseye-updates main non-free contrib deb-src https://mirrors.aliyun.com/debian bullseye-proposed-updates main non-free contrib deb-src https://mirrors.aliyun.com/debian bullseye-backports main non-free contrib deb-src https://mirrors.aliyun.com/debian bullseye-backports-sloppy main non-free contrib # 阿里安全更新镜像源 deb https://mirrors.aliyun.com/debian-security bullseye-security main non-free contrib deb-src https://mirrors.aliyun.com/debian-security bullseye-security main non-free contribhttps://blog.csdn.net/mumoing/article/details/130169777
执行 apt update 命令更新软件索引
参考：
安装net-tools
sudo apt-get install net-tools
