1.更新源的步骤

(1)备份原来的源列表文件 cd /etc/apt/ mv sources.list sources.list.bak

(2)新建源文件,输入源地址 nano sources.list 在nano sources.list输入如下源地址

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

 

然后按ctrl+o保存,然后ctrl+x退出

(3)删除旧的源文件 rm /var/lib/apt/lists/* rm /var/lib/apt/lists/partial/*

(4)最后更新源文件 apt-get update 到此更新源成功