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 dapper main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb 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 dapper main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb 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 dapper main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb dapper main restricted universe multiverse
deb
http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src dapper main restricted universe multiverse
deb-src dapper-security main restricted universe multiverse
deb-src dapper-updates main restricted universe multiverse
deb-src 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（教育网，推荐校园网和网通用户使用。）：
deb dapper main multiverse restricted universe
deb dapper-backports main multiverse restricted universe
deb dapper-proposed main multiverse restricted universe
deb dapper-security main multiverse restricted universe
deb dapper-updates main multiverse restricted universe
deb 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 dapper main multiverse restricted universe
deb dapper-backports main multiverse restricted universe
deb dapper-proposed main multiverse restricted universe
deb dapper-security main multiverse restricted universe
deb dapper-updates main multiverse restricted universe
deb 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。）
deb dapper main restricted universe multiverse
deb-src dapper main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb-src dapper-updates main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb-src dapper-backports main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb-src dapper-security main restricted universe multiverse
deb dapper main multiverse restricted universe
Mirror.vmmatrix.net 更新服务器（上海市电信，推荐电信网通用户使用。）:
deb dapper main restricted universe multiverse
deb-src dapper main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb-src dapper-updates main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb-src dapper-backports main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb-src dapper-security main restricted universe multiverse
deb dapper main multiverse restricted universe
ubuntu.cnsite.org 更新服务器 (福建省福州市 电信):
deb dapper main restricted universe multiverse
deb-src dapper main restricted universe multiverse
deb dapper-updates main restricted universe multiverse
deb-src dapper-updates main restricted universe multiverse
deb dapper-backports main restricted universe multiverse
deb-src dapper-backports main restricted universe multiverse
deb dapper-security main restricted universe multiverse
deb-src dapper-security main restricted universe multiverse
deb dapper main multiverse restricted universe
到以下网址可以自定义产生若干源： 以下网址有极其全面的源，以供补充：
.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
sudo apt-get dist-upgrade
