sudo rm -rf /etc/apt/sources.list sudo vi /etc/apt/sources.list 163(推荐)： # 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 http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse # deb-src http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse # deb-src http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse # deb-src http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse # deb-src http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse # 预发布软件源，不建议启用 # deb http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse # deb-src http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse 阿里： 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-proposed main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse