Debian 更换国内清华源
1、备份原文件mv /etc/apt/sources.list /etc/apt/sources.list.old
2、写入新源，以下是 Debian 11 的：

cat > /etc/apt/sources.list << EOF
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-free
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-freedeb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-free
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-freedeb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-free
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-freedeb https://mirrors.tuna.tsinghua.edu.cn/debian-security/ bullseye-security main contrib non-free
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian-security/ bullseye-security main contrib non-free
EOF

如果是 Debian 12：

cat > /etc/apt/sources.list << EOF
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm main contrib non-free non-free-firmware
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm main contrib non-free non-free-firmwaredeb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-updates main contrib non-free non-free-firmware
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-updates main contrib non-free non-free-firmwaredeb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-backports main contrib non-free non-free-firmware
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-backports main contrib non-free non-free-firmwaredeb https://mirrors.tuna.tsinghua.edu.cn/debian-security bookworm-security main contrib non-free non-free-firmware
deb-src https://mirrors.tuna.tsinghua.edu.cn/debian-security bookworm-security main contrib non-free non-free-firmware
EOF

注：
1、deb 指向的是编译好的二进制软件包。
deb-src 指向的是软件的源代码包，可以使用apt source命令下载软件的源代码并自行编译。
2、在Debian系统添加 清华 docker 源方便安装 docker

deb https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/debian bookworm stable

3、在Debian系统上查看可用的Docker版本，可以使用以下命令：
apt-cache madison docker-ce
这个命令会列出docker-ce（社区版）的所有可用版本。

apt-cache madison docker-ce

4、其它 Dibian 源
8个 Debian 国内镜像源整理 提高服务器软件安装速度
参见：https://www.jianshu.com/p/b597283b27aa
5、Ubuntu 22.04 清华源配置
注释掉原有的源地址，并添加清华源地址。以下是一个示例配置，适用于Ubuntu 22.04 (Jammy Jellyfish)：

deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-security main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse

6、Ubuntu 24.04 清华源配置
在 Ubuntu 24.04 之前，Ubuntu 的软件源配置文件使用传统的 One-Line-Style，路径为 /etc/apt/sources.list；从 Ubuntu 24.04 开始，Ubuntu 的软件源配置文件变更为 DEB822 格式，路径为 /etc/apt/sources.list.d/ubuntu.sources。
将系统自带的对应文件做个备份，然后根据格式的选择下面对应的内容替换，即可使用选择的软件源镜像。
具体参见：https://mirror.tuna.tsinghua.edu.cn/help/ubuntu/