Ubuntu20.04

#!/bin/bash

# 备份原有的软件源列表文件
sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup.$(date +%Y%m%d%H%M%S)

# 写入阿里云的 Ubuntu 20.04 (focal) 镜像源
sudo tee /etc/apt/sources.list << 'EOF'
# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb https://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
# deb-src https://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb https://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
# deb-src https://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb https://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
# deb-src https://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
# deb https://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
# deb-src https://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
deb https://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
# deb-src https://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
EOF

# 更新软件包列表
sudo apt update