Ubuntu 安装好后默认的是官方的源，这当然是一个有效的源：但其缺点就是一个字--"慢"!!所以我们应该换一个更适合我们的有效源。
源的更换是通过更新系统源列表文件sources.list 实现的：先用命令sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup 备份官方的源列表文件[以防我们新配的源不可用，当然自信的你不配分也罢O(∩_∩)O~]。cp 是copy[拷贝] 的缩写，这条命令的作用即把/etc/apt/ 目录下的sources.list 文件拷贝一个备份到当前目录，备份的文件名为sources.list_backup。
Ubuntu 安装好后默认的是官方的源，这当然是一个有效的源：但其缺点就是一个字--"慢"!!所以我们应该换一个更适合我们的有效源。
源的更换是通过更新系统源列表文件sources.list 实现的：先用命令sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup 备份官方的源列表文件[以防我们新配的源不可用，当然自信的你不配分也罢O(∩_∩)O~]。cp 是copy[拷贝] 的缩写，这条命令的作用即把/etc/apt/ 目录下的sources.list 文件拷贝一个备份到当前目录，备份的文件名为sources.list_backup。
接着我们用命令sudo gedit /etc/apt/sources.list [命令中的gedit 是一个文本编辑器，意即用gedit 编辑/etc/apt/ 目录下的源列表sources.list 文件，sudo 是取得权限的命令]编辑你的源列表文件：将原来的内容全部删除，选择一个适合您的源添加到源列表文件sources.list 中，然后保存您列表。
北 交 大：[笔者测试的速度很好，接近1M/s ，推荐教育网用户使用O(∩_∩)O~]
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-backports main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-proposed main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-security main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-updates main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-backports main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-proposed main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-security main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-updates main multiverse restricted universe
日 本 源：[笔者测试的速度还好，在200kb/s 左右，算是比较快的O(∩_∩)O~]
deb http://security.ubuntu.com/ubuntu/ karmic-security universe main multiverse restricted
deb-src http://jp.archive.ubuntu.com/ubuntu/ karmic-security universe main multiverse restricted
deb http://jp.archive.ubuntu.com/ubuntu/ karmic main universe restricted multiverse
deb-src http://jp.archive.ubuntu.com/ubuntu/ karmic main universe restricted multiverse
deb http://jp.archive.ubuntu.com/ubuntu/ karmic-updates universe main multiverse restricted
deb-src http://jp.archive.ubuntu.com/ubuntu/ karmic-updates universe main multiverse restricted
deb http://jp.archive.ubuntu.com/ubuntu/ karmic-proposed universe main multiverse restricted
deb-src http://jp.archive.ubuntu.com/ubuntu/ karmic-proposed universe main multiverse restricted
台 湾 源：[笔者测试的速度还好，比上个源稍微慢点，也算是比较快的了~]
deb http://security.ubuntu.com/ubuntu/ karmic-security universe main multiverse restricted
deb-src http://tw.archive.ubuntu.com/ubuntu/ karmic-security universe main multiverse restricted
deb http://tw.archive.ubuntu.com/ubuntu/ karmic main universe restricted multiverse
deb-src http://tw.archive.ubuntu.com/ubuntu/ karmic main universe restricted multiverse
deb http://tw.archive.ubuntu.com/ubuntu/ karmic-updates universe main multiverse restricted
deb-src http://tw.archive.ubuntu.com/ubuntu/ karmic-updates universe main multiverse restricted
deb http://tw.archive.ubuntu.com/ubuntu/ karmic-proposed universe main multiverse restricted
deb-src http://tw.archive.ubuntu.com/ubuntu/ karmic-proposed universe main multiverse restricted
江苏双线：[笔者测试很慢，只有几kb/s 但电信用户应该较这个速度要快~]
deb http://mirror.lupaworld.com/ubuntu karmic main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu karmic-security main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu karmic-updates main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu karmic-backports main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu/ubuntu-cn karmic main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu/ karmic-proposed main restricted universe multiverse
deb-src http://mirror.lupaworld.com/ubuntu karmic main restricted universe multiverse
deb-src http://mirror.lupaworld.com/ubuntu karmic-security main restricted universe multiverse
deb-src http://mirror.lupaworld.com/ubuntu karmic-updates main restricted universe multiverse
deb-src http://mirror.lupaworld.com/ubuntu karmic-backports main restricted universe multiverse
deb-src http://mirror.lupaworld.com/ubuntu/ karmic-proposed main restricted universe multiverse
换好源后，应先后执行sudo apt-get update 和sudo apt-get upgrade 命令[在文章开头提到的文章里，笔者并没有要求一定执行sudo apt-get upgrade 命令，这是因为这条命令是可选的命令，即一定要执行sudo apt-get update 但可以不执行sudo apt-get upgrade 命令，这又是为什么呢？]
原因所在：
sudo apt-get update 命令用来更新源：这指令执行后取得记录在/etc/apt/sources.list 内的远端服务器的套件档案清单[注意，是清单!这是系统获得更新的前提]。而sudo apt-get upgrade 是用来获得清单里面的软件[当然此说法不是很准确，但也不能说它是绝对错的--为省掉不必要的罗嗦就这么说了，总之知道这个就行了O(∩_∩)O~]
分享交流：ubuntu 10.04 Lucid 更新源列表，适合国内大部分电信、网通用户
台湾官方源，适合国内大部分网通电信用户。一般在百来K 左右吧～～（我是教育网没法测试～）
deb http://tw.archive.ubuntu.com/ubuntu/ lucid main universe restricted multiverse
deb-src http://tw.archive.ubuntu.com/ubuntu/ lucid main universe restricted multiverse
deb http://tw.archive.ubuntu.com/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://tw.archive.ubuntu.com/ubuntu/ lucid-security universe main multiverse restricted
deb http://tw.archive.ubuntu.com/ubuntu/ lucid-updates universe main multiverse restricted
deb-src http://tw.archive.ubuntu.com/ubuntu/ lucid-updates universe main multiverse restricted
骨头源：（一个热爱开源事业的网友搭建的，口碑很好，速度自己测试就知道了～呵呵！）
deb http://ubuntu.srt.cn/ubuntu/ lucid main universe restricted multiverse
deb-src http://ubuntu.srt.cn/ubuntu/ lucid main universe restricted multiverse
deb http://ubuntu.srt.cn/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-security universe main multiverse restricted
deb http://ubuntu.srt.cn/ubuntu/ lucid-updates universe main multiverse restricted
deb http://ubuntu.srt.cn/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://ubuntu.srt.cn/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://ubuntu.srt.cn/ubuntu/ lucid-updates universe main multiverse restricted
163网易更新源：
deb http://mirrors.163.com/ubuntu/ lucid main universe restricted multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid main universe restricted multiverse
deb http://mirrors.163.com/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-security universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirrors.163.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.163.com/ubuntu/ lucid-updates universe main multiverse restricted
sohu 搜狐更新源：
deb http://mirrors.shlug.org/ubuntu/ lucid main universe restricted multiverse
deb-src http://mirrors.shlug.org/ubuntu/ lucid main universe restricted multiverse
deb http://mirrors.shlug.org/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirrors.shlug.org/ubuntu/ lucid-security universe main multiverse restricted
deb http://mirrors.shlug.org/ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirrors.shlug.org/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirrors.shlug.org/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirrors.shlug.org/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.shlug.org/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.shlug.org/ubuntu/ lucid-updates universe main multiverse restricted
ubuntu 上海官方源（推荐上海电信用户使用）
deb http://mirror.rootguide.org/ubuntu/ lucid main universe restricted multiverse
deb-src http://mirror.rootguide.org/ubuntu/ lucid main universe restricted multiverse
deb http://mirror.rootguide.org/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirror.rootguide.org/ubuntu/ lucid-security universe main multiverse restricted
deb http://mirror.rootguide.org/ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirror.rootguide.org/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirror.rootguide.org/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirror.rootguide.org/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirror.rootguide.org/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirror.rootguide.org/ubuntu/ lucid-updates universe main multiverse restricted
江苏双线 LUPAWorld 源:
deb-src http://mirror.lupaworld.com/Ubuntu/ lucid main universe restricted multiverse
deb http://mirror.lupaworld.com/Ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirror.lupaworld.com/Ubuntu/ lucid-security universe main multiverse restricted
deb http://mirror.lupaworld.com/Ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirror.lupaworld.com/Ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirror.lupaworld.com/Ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirror.lupaworld.com/Ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirror.lupaworld.com/Ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirror.lupaworld.com/Ubuntu/ lucid-updates universe main multiverse restricted
备份：sudo cp /etc/apt/sources.list etc/apt/sources_backup.list
备不备份无所谓了sudo gedit /etc/apt/sources.list 清空后直接添加下列任一源列表保存后sudo apt-get update,OK。
