1.
首先备份源列表:
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
2.
清空原来的/etc/apt/sources.list，添加网易的源列表
deb http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
3.
刷新列表:
sudo apt-get update
vim显示行号
vi /etc/vim/vimrc
set nu
deb http://cn.archive.ubuntu.com/ubuntu/ xenial main restricted
deb http://cn.archive.ubuntu.com/ubuntu/ xenial universe
deb http://cn.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://download.virtualbox.org/virtualbox/debian xenial contrib