写在前面：小F浏览了很多国内外的网站，看了很多关于软件源(Software Sources)设置的文章，发现有很多文章中对软件源的设置存在误解，为了让新人能顺利进入Ubuntu的大家庭，小F特地作此文，详细地介绍下软件源的设置。
1、软件源(Software Sources)是什么？在Ubuntu中，软件源是指一个由可以获得软件的地址组成的集合，这个地址可以是网站、光盘，或者是硬盘上的一个目录。软件源上有“软件仓库”，软件 仓库中存储着各种各样的软件。当你需要用到一个软件的时候，就可以通过工具（新立得synaptic 、 apt-get 或者aptitude 等），自动地下载并自动地安装。
2、软件源(Software Sources)设置好了，我可以获得哪些便利？日常的软件安装或者更新都是采用从软件源获取软件包的方式。设置好软件源可以让你及时获取重要的安全更新，解决安全隐患;或者修复已知的问题，让使用更顺手。设置好软件源同样可以加快以上操作的速度，节约你宝贵的时间。
3、我是新手，我不会设置，有简单的图形化界面的设置方法吗？Ubuntu的系统(System)-系统管理(Administration)菜单里提供了图形化界面的软件源设置(Software Sources)程序，不过小F提醒一下大家，只使用这个是不够的！（具体设置方法请继续往下看）
4、正确的设置方法！在开始修改设置之前，先备份一下原来的设置。这一步看似多余，其实是一种很好的习惯，有利于配置错误时的恢复。备份方法是：按Alt+F2，然后输入 gksu cp /etc/apt/sources.list /etc/apt/sources.list-backup。回车后输入你的密码。
然后打开设置程序：系统(System)-系统管理(Administration)-软件源设置(SoftwareSources)。在第一个标签页上，单击“下载自(DownloadFrom)”右边的菜单，选择“其他…(Others…)”。然后在弹出的窗口中单击“选择最佳服务器(Select BestServer)”。下面系统会自动ping官方服务器列表中的服务器，并选择最快的！
再按Alt+F2打开“运行程序(Run Application)”，输入 gksu gedit /etc/apt/sources.list。回车后如果有提示输入密码，输入你的密码。把光标调到文件的最后。
（1）电信用户加入下面的内容：
deb hardy main restricted universe multiversedeb hardy-security main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb hardy-proposed main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb-src hardy-proposed main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy main restricted universe multiversedeb hardy main restricteddeb-src hardy restricted main universedeb hardy universedeb hardy-updates universedeb-src hardy-updates universedeb hardy main restricteddeb-src hardy restricted main universedeb hardy universedeb hardy-updates universedeb-src hardy-updates universe #Added by software-propertiesdeb
http://security.ubuntu.com/ubuntu hardy-security main restricteddeb-src
http://security.ubuntu.com/ubuntu hardy-security restricted main universedeb
http://security.ubuntu.com/ubuntu hardy-security universe
（2）网通/教育网用户加入下面的内容：
deb hardy main restricted universe multiversedeb-src hardy main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy-security main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb hardy-proposed main multiverse restricted universedeb-src hardy-proposed main restricted universe multiversedeb hardy main restricted universe multiversedeb hardy main restricteddeb-src hardy restricted main universedeb hardy universedeb hardy-updates universedeb-src hardy-updates universedeb hardy main restricteddeb-src hardy restricted main universedeb hardy universedeb hardy-updates universedeb-src hardy-updates universe #Added by software-propertiesdeb
http://security.ubuntu.com/ubuntu hardy-security main restricteddeb-src
http://security.ubuntu.com/ubuntu hardy-security restricted main universedeb
http://security.ubuntu.com/ubuntu hardy-security universe
然后按Ctrl+S保存文档，关掉这个窗口。
5、为什么我要设置这么多国外源？Ubuntu的项目是由世界各地的爱好者共同维护的，因此服务器端文件的更新很难做到同步。由于Ubuntu的主服务器在欧洲，项目小组在挪威国，而英语是Ubuntu用户中使用最广的语言，因此最新的更新版本很快被发布到Ubuntu的欧洲主源和美国源。同时国内的Ubuntu更新源经常存在软件包缺失的问题，因此小F推荐大家设置欧洲和美国的官方源。
6、源越多速度越快吗？很不幸，Ubuntu的软件管理程序没有自动判断最快源的功能。因此无论你设置了多少源，Ubuntu只按照源列表的顺序，找到第一个提供相应软件包下载的源并连接下载。因此我们在设置的时候让Ubuntu先自动找最快的源，然后把可能作为补充的源加在后面。相反地，设置的源过多，反而会降低更新 (apt-get update)的速度。
附录：官方源列表中没有的常用软件源列表（可以自己试试哪个更快，但是不要去掉国外源）
Ubuntu.cn99.com更新服务器（江苏省常州市电信，推荐电信用户使用）：
deb hardy main restricted universe multiversedeb hardy-security main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb hardy-proposed main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb-src hardy-proposed main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy main restricted universe multiverse
Mirror.lupaworld.com更新服务器（浙江省杭州市双线服务器）：
deb hardy main restricted universe multiversedeb hardy-security main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb hardy-proposed main restricted universe multiversedeb-src hardy main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb-src hardy-proposed main restricted universe multiverse
厦门大学更新服务器（教育网服务器）：
deb hardy main restricted universe multiversedeb hardy-backports restricted universe multiversedeb hardy-proposed main restricted universe multiversedeb hardy-security main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb-src hardy main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb-src hardy-proposed main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb-src hardy-updates main restricted universe multiverse
成都市 电子科技大学更新服务器（教育网，推荐校园网和网通用户使用）：
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
== 如果无法解析uestc.edu.cn域名，请使用以下地址 ==
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
上海市上海交通大学更新服务器（教育网，推荐校园网和网通用户使用）：
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
中国科学技术大学更新服务器（教育网，推荐校园网和网通用户使用）：
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
北京市清华大学更新服务器（教育网，推荐校园网和网通用户使用）：
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
沈阳市东北大学更新服务器（教育网，推荐校园网和网通用户使用）：
deb hardy main multiverse restricted universedeb hardy-backports main multiverse restricted universedeb hardy-proposed main multiverse restricted universedeb hardy-security main multiverse restricted universedeb hardy-updates main multiverse restricted universedeb-src hardy main multiverse restricted universedeb-src hardy-backports main multiverse restricted universedeb-src hardy-proposed main multiverse restricted universedeb-src hardy-security main multiverse restricted universedeb-src hardy-updates main multiverse restricted universe
中国台湾 台湾大学更新服务器（推荐网通用户使用，电信PING平均响应速度41MS。强烈推荐此源，比较完整，较少出现同步问题）：
deb hardy main restricted universe multiversedeb-src hardy main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy-security main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb hardy-proposed main multiverse restricted universedeb-src hardy-proposed main restricted universe multiverse
Mirror.vmmatrix.net更新服务器（上海市电信，推荐电信网通用户使用）：
deb hardy main restricted universe multiversedeb-src hardy main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy-security main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb hardy-proposed main multiverse restricted universedeb-src hardy-proposed main restricted universe multiverse
ubuntu.cnsite.org更新服务器（福建省福州市 电信）：
deb hardy main restricted universe multiversedeb-src hardy main restricted universe multiversedeb hardy-updates main restricted universe multiversedeb-src hardy-updates main restricted universe multiversedeb hardy-backports main restricted universe multiversedeb-src hardy-backports main restricted universe multiversedeb hardy-security main restricted universe multiversedeb-src hardy-security main restricted universe multiversedeb hardy-proposed main multiverse restricted universedeb-src hardy-proposed main restricted universe multiverse
感谢
Felix的投递
