Ubuntu更换国内源提高包管理器下载速度

问题

Ubuntu配置的默认源并不是国内的服务器，下载更新软件都比较慢。

解决

1. 首先备份源列表

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

2. 打开sources.list文件修改。选择合适的源，替换原文件的内容，保存编辑好的文件, 以阿里云更新服务器为例（可以分别测试阿里云、清华、中科大、163源的速度，选择最快的）：

   sudo gedit /etc/apt/sources.list

   编辑/etc/apt/sources.list文件, 在文件最前面添加阿里云镜像源：

   #  阿里源
   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

3. 刷新列表

   sudo apt-get update
   sudo apt-get upgrade
   sudo apt-get install build-essential

参考：

1. https://zhuanlan.zhihu.com/p/61228593