修改源并更新升级Ubuntu

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

• Archive.ubuntu.com 更新服务器(欧洲，此为官方源，推荐使用。)：

deb http://archive.ubuntu.com/ubuntu/ edgy main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ edgy-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ edgy-updates main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ edgy-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ edgy main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ edgy-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ edgy-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ edgy-backports main restricted universe multiverse
deb http://archive.ubuntu.org.cn/ubuntu-cn/ edgy 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/ edgy main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-security main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-updates main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ edgy-backports main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-security main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-updates main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-proposed main restricted universe multiverse
deb-src http://ubuntu.cn99.com/ubuntu/ edgy-backports main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu-cn/ edgy 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 edgy main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu edgy-security main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu edgy-updates main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu edgy-backports main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu edgy-proposed main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu edgy main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu edgy-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu edgy-updates main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu edgy-backports main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu edgy-proposed main restricted universe multiverse
deb http://mirror.lupaworld.com/ubuntu/ubuntu-cn edgy 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。）(目前已无法使用)：

deb http://ftp.sjtu.edu.cn/ubuntu/ edgy main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ edgy-backports main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ edgy-proposed main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ edgy-security main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ edgy-updates main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ edgy main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ edgy-backports main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ edgy-proposed main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ edgy-security main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ edgy-updates main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ edgy 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/ edgy main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ edgy-backports main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ edgy-proposed main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ edgy-security main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu/ edgy-updates main multiverse restricted universe
deb-src http://mirror9.net9.org/ubuntu/ edgy main multiverse restricted universe
deb-src http://mirror9.net9.org/ubuntu/ edgy-backports main multiverse restricted universe
deb-src http://mirror9.net9.org/ubuntu/ edgy-proposed main multiverse restricted universe
deb-src http://mirror9.net9.org/ubuntu/ edgy-security main multiverse restricted universe
deb-src http://mirror9.net9.org/ubuntu/ edgy-updates main multiverse restricted universe
deb http://mirror9.net9.org/ubuntu-cn/ edgy 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/ edgy main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-updates main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-updates main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-backports main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-backports main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-security main restricted universe multiverse
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-security main restricted universe multiverse
deb http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-proposed main multiverse restricted universe
deb-src http://ubuntu.csie.ntu.edu.tw/ubuntu/ edgy-proposed main restricted universe multiverse
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ edgy 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。）(目前已无法使用):

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

sudo apt-get update
sudo apt-get dist-upgrade