• 不 同的网络状况连接以下源的速度不同，所以cn99并不一定是最快的源。建议在添加前手动验证以下源的连接速度(ping下就行)，比如说北京网通用户连接 cn99就非常慢，而ftp.sjtu.edu.cn是相对较快的源，选择最快的源可大大节省下载时间，请根据自己网络环境设置更新服务器，以达到最快的 速度。（经试验，执行下文中需要的apt-get命令或使用《新立得软件包管理器》时，必须更改了默认的更新服务器才可以使用，否则可能找不到很多安装 包，或者安装包版本低。）

‘注意，你可以同时加入几个源。或者将官方的源(也就是下面的Archive.ubuntu.com的条目)直接加在文件的最后，以避免出现 404 Not Found 文件未发现 的错误。’建议电信用户使用cn99和台湾大学的源,建议网通用户使用台湾大学的源.

• 在终端执行以下命令（第一条是备份现有服务器列表，第二条是使用Gedit编辑，您也可以使用自己喜爱的编辑器编辑。）

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

sudo gedit /etc/apt/sources.list

• 从以下各服务器列表内容中选择一段替换文件中的所有内容（请根据自己网络环境设置更新服务器，以达到最快的速度。）

Archive.ubuntu.com 更新服务器(欧洲)：

deb http://archive.ubuntu.com/ubuntu/ dapper main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-updates main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ dapper-backports main restricted universe multiverse
deb http://archive.ubuntu.org.cn/ubuntu-cn/ dapper main restricted universe multiverse

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 http://ubuntu.cn99.com/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-security main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu-cn/ dapper main restricted universe multiverse

Mirror.lupaworld.com 更新服务器(浙江省杭州市电信，亚洲地区官方更新服务器，推荐全国用户使用。）：

deb http://cn.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu/ubuntu-cn dapper main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse

上海市 上海交通大学 更新服务器（推荐教育网和网通用户使用。）

deb http://ftp.sjtu.edu.cn/ubuntu/ dapper main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-backports main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-proposed main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-security main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ dapper-updates main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper 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 http://mirror9.net9.org/ubuntu/ dapper main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ dapper-backports main multiverse restricted universe deb http://mirror9.net9.org/ubuntu/ dapper-proposed main multiverse restricted universe deb http://mirror9.net9.org/ubuntu/ dapper-security main multiverse restricted universe deb http://mirror9.net9.org/ubuntu/ dapper-updates main multiverse restricted universe deb http://mirror9.net9.org/ubuntu-cn/ dapper main multiverse restricted universe

中国 台湾省台湾大学 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 http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ dapper-security main restricted universe multiverse
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper main multiverse restricted universe

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.vmmatrix.net 更新服务器（上海市电信，推荐电信网通用户使用。）(目前已无法使用):

deb http://mirror.vmmatrix.net/ubuntu/ dapper main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-updates main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-backports main restricted universe multiverse
deb http://mirror.vmmatrix.net/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://mirror.vmmatrix.net/ubuntu/ dapper-security main restricted universe multiverse
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ dapper main multiverse restricted universe

ubuntu.cnsite.org 更新服务器 (福建省福州市 电信)

deb http://ubuntu.cnsite.org/ubuntu/ dapper main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-updates main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-backports main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://ubuntu.cnsite.org/ubuntu/ dapper-security main restricted universe multiverse
deb http://ubuntu.cnsite.org/ubuntu-cn/ dapper main multiverse restricted universe

mirror.rootguide.org 更新服务器 (上海市 电信):(推荐教育网用户使用)

deb http://mirror.rootguide.org/ubuntu/ dapper main restricted universe multiverse
deb-src http://mirror.rootguide.org/ubuntu/ dapper main restricted universe multiverse
deb http://mirror.rootguide.org/ubuntu/ dapper-updates main restricted universe multiverse
deb-src http://mirror.rootguide.org/ubuntu/ dapper-updates main restricted universe multiverse
deb http://mirror.rootguide.org/ubuntu/ dapper-backports main restricted universe multiverse
deb-src http://mirror.rootguide.org/ubuntu/ dapper-backports main restricted universe multiverse
deb http://mirror.rootguide.org/ubuntu/ dapper-security main restricted universe multiverse
deb-src http://mirror.rootguide.org/ubuntu/ dapper-security main restricted universe multiverse
deb http://mirror.rootguide.org/ubuntu/ dapper-proposed main multiverse restricted universe
deb-src http://mirror.rootguide.org/ubuntu/ dapper-proposed main restricted universe multiverse
deb http://mirror.rootguide.org/ubuntu-cn/ dapper main multiverse restricted universe

到以下网址可以自定义产生若干源：

http://www.ubuntulinux.nl/source-o-matic

以下网址有极其全面的源，以供补充：

http://italy.copybase.ch/blog/lista-repository-sourceslist-ottimizzata-per-ubuntu-kubuntu-linux/

• 保存编辑好的文件，执行以下命令更新。

  sudo apt-get update #这一步是更新你的源列表，换源后必须执行

sudo apt-get dist-upgrade #这一步是更新软件，如果你对新版本软件的需求不是那么迫切，可以不执行