西安交通大学软件镜像站 Ubuntu 镜像源、Ubuntu Releases 镜像源与 Ubuntu Ports 镜像源使用帮助。
选择 Ubuntu 版本：
# Config generated by XJTU Mirrors Config Generator; DO NOT EDIT.deb https://mirrors.xjtu.edu.cn/ubuntu/ focal main restricted universe multiverse# deb-src https://mirrors.xjtu.edu.cn/ubuntu/ focal main restricted universe multiversedeb https://mirrors.xjtu.edu.cn/ubuntu/ focal-updates main restricted universe multiverse# deb-src https://mirrors.xjtu.edu.cn/ubuntu/ focal-updates main restricted universe multiversedeb https://mirrors.xjtu.edu.cn/ubuntu/ focal-backports main restricted universe multiverse# deb-src https://mirrors.xjtu.edu.cn/ubuntu/ focal-backports main restricted universe multiversedeb https://mirrors.xjtu.edu.cn/ubuntu/ focal-security main restricted universe multiverse# deb-src https://mirrors.xjtu.edu.cn/ubuntu/ focal-security main restricted universe multiverse# deb https://mirrors.xjtu.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse# deb-src https://mirrors.xjtu.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse