一、使用Shell脚本

脚本操作指南参见：Ubuntu Shell 脚本操作

update_sources.sh

#!/bin/bash

# 备份sources.list文件
sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup

# 修改sources.list文件
sudo bash -c 'cat > /etc/apt/sources.list' <<EOF
deb http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
EOF

# 更新软件包列表并升级
sudo apt update -y
sudo apt upgrade -y

# 自动移除不需要的软件包
sudo apt autoremove -y

二、手动操作

1. 备份原文件

sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup

2. 修改/etc/apt/sources.list

将原内容全部删除，替换为想要的源内容。

  • Ubuntu 20.04 官方源

deb http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse

Ubutnu 其他版本可以将focal替换为相应的版本代号：

版本

代号

源关键字

20.04

Focal Fossa

focal

21.04

Hirsute Hippo

hirsute

22.04

Jammy Jellyfish

jammy

3. 更新并使能

更新可用软件列表，并升级已安装软件到最新版本。

sudo apt update && sudo apt upgrade

4. 卸载不再需要的软件包

此命令同时也会删除这些软件包安装时自动安装的但现在不再需要的依赖包。

sudo apt autoremove