用java几年，最近想了解一下Python，打算安装Ubuntu系统，Ubuntu系统安装难免遇到一些问题，再次罗列
问题：Ubuntu系统安装，前部分有部分文件和命令的下载，如果不使用国内镜像文件，下载速度非常慢，这时就需要考虑更换镜像（推荐阿里的镜像）
补充（虚拟机用vm virtualbox ）
镜像文件修改路径：vim /etc/apt/sources.list ， 如果更改之前需要做保存，可以用cp /etc/apt/sources.list /etc/apt/sources.back
后添加阿里镜像：
deb http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse
当然，如果你想使用其他镜像，也可考虑，这里也做一下备注#网易163
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
#台湾的官方源 deb http://tw.archive.ubuntu.com/ubuntu gutsy main restricted universe multiverse deb http://tw.archive.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse deb http://tw.archive.ubuntu.com/ubuntu gutsy-updates main restricted universe multiverse deb http://tw.archive.ubuntu.com/ubuntu gutsy-backports main restricted universe multiverse deb http://tw.archive.ubuntu.com/ubuntu gutsy-proposed main restricted universe multiverse deb-src http://tw.archive.ubuntu.com/ubuntu gutsy main restricted universe multiverse deb-src http://tw.archive.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse deb-src http://tw.archive.ubuntu.com/ubuntu gutsy-updates main restricted universe multiverse deb-src http://tw.archive.ubuntu.com/ubuntu gutsy-backports main restricted universe multiverse deb-src http://tw.archive.ubuntu.com/ubuntu gutsy-proposed main restricted universe multiverse
#Mirror.lupaworld.com 源更新服务器（浙江省杭州市双线服务器，网通同电信都可以用，亚洲地区官方更新服务器）：
deb http://mirror.lupaworld.com/ubuntu gutsy main restricted universe multiverse deb http://mirror.lupaworld.com/ubuntu gutsy-security main restricted universe multiverse deb http://mirror.lupaworld.com/ubuntu gutsy-updates main restricted universe multiverse deb http://mirror.lupaworld.com/ubuntu gutsy-backports main restricted universe multiverse deb-src http://mirror.lupaworld.com/ubuntu gutsy main restricted universe multiverse deb-src http://mirror.lupaworld.com/ubuntu gutsy-security main restricted universe multiverse deb-src http://mirror.lupaworld.com/ubuntu gutsy-updates main restricted universe multiverse deb-src http://mirror.lupaworld.com/ubuntu gutsy-backports main restricted universe multiverse
#cn99.com 源更新服务器（江苏省常州市电信，推荐电信用户使用）： deb http://ubuntu.cn99.com/ubuntu/ gutsy main restricted universe multiverse deb http://ubuntu.cn99.com/ubuntu/ gutsy-security main restricted universe multiverse deb http://ubuntu.cn99.com/ubuntu/ gutsy-updates main restricted universe multiverse deb http://ubuntu.cn99.com/ubuntu/ gutsy-proposed main restricted universe multiverse deb http://ubuntu.cn99.com/ubuntu/ gutsy-backports main restricted universe multiverse deb-src http://ubuntu.cn99.com/ubuntu/ gutsy main restricted universe multiverse deb-src http://ubuntu.cn99.com/ubuntu/ gutsy-security main restricted universe multiverse deb-src http://ubuntu.cn99.com/ubuntu/ gutsy-updates main restricted universe multiverse deb-src http://ubuntu.cn99.com/ubuntu/ gutsy-proposed main restricted universe multiverse deb-src http://ubuntu.cn99.com/ubuntu/ gutsy-backports main restricted universe multiverse
可能有些同志在修改文件时出现此错误：（没有修改权限）此时的你会一脸闷逼，明明自己的角色是超级管理员（root）为啥不行。
接下来你可能需要操作此命令
经常是用vim打开了某个/etc下的文件，使用 :w 保存的时候提示 "E45: 'readonly' option is set (add ! to override)"，而 :w! 则提示 "E212: Can't open file for writing"。
通常的解决方案是 :q!
退出后，在命令行里输和：sudo !!
再次vim ...编辑，
再:/wq，就可以了。
然后更新源：
sudo apt-get update
. 更新软件
sudo apt-get update
然后你就会发现，下载更新速度，快了N倍