在 Ubuntu 系统中，将 APT 源设置为阿里云源可以提高软件包更新和下载速度。

设置国内源

1. 备份现有的源列表：

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

2. 编辑 sources.list 文件：

使用以下命令打开 sources.list 文件：

sudo vi /etc/apt/sources.list

3. 替换内容为阿里源：

根据Ubuntu 版本，将内容替换为对应的阿里源。以下是常见版本的源地址：

Ubuntu (Jammy):

deb http://mirrors.aliyun.com/ubuntu/ jammy main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-proposed main restricted universe multiverse

Ubuntu (Focal):

deb http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse

Ubuntu (Bionic):

deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

编辑完成后，保存并退出：

4. 更新软件包索引：

使用以下命令更新软件包索引：

sudo apt update

查找各种版本的包

可以在 https://launchpad.net/ubuntu/ 上查找对应版本的代码和二进制

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