修改前记得先备份
sudo cp /etc/apt/sources.list /etc/apt/sources.bak
然后修改源配置文件
sudo gedit /etc/apt/sources.list
#中科大ubuntu 更新服务器
deb http://debian.ustc.edu.cn/ubuntu/ lucid main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ lucid-security main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ lucid-updates main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ lucid-backports main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-security main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-updates main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-backports main restricted universe multiverse
------以下的源,我尝试过,用不起来了-------
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
rootguide源，Ubuntu官方上海源，提供 Kernel，Hiweed，ubuntu
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
网易开源镜像站,提供FreeBSD，OpenBSD，archlinux，centos，cygwin，debian，Fedora，gentoo，kernel，openSUSE，slackware，Ubuntu
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
搜狐开源镜像站，提供 CPAN，FreeBSD，NetBSD，OpenBSD，apache，archlinux，centos，cygwin，dag，debian，Fedora，gentoo，kernel，lfs，mysql，nginx，openSUSE，php，rpmfusion，slackware，Ubuntu
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
搜狐开源镜像站，提供 CPAN，FreeBSD，NetBSD，OpenBSD，apache，archlinux，centos，cygwin，dag，debian，Fedora，gentoo，kernel，lfs，mysql，nginx，openSUSE，php，rpmfusion，slackware，Ubuntu
deb http://mirrors.sohu.com/Ubuntu/ lucid main universe restricted multiverse
deb-src http://mirrors.sohu.com/Ubuntu/ lucid main universe restricted multiverse
deb http://mirrors.sohu.com/Ubuntu/ lucid-security universe main multiverse restricted
deb-src http://mirrors.sohu.com/Ubuntu/ lucid-security universe main multiverse restricted
deb http://mirrors.sohu.com/Ubuntu/ lucid-updates universe main multiverse restricted
deb http://mirrors.sohu.com/Ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://mirrors.sohu.com/Ubuntu/ lucid-proposed universe main multiverse restricted
deb http://mirrors.sohu.com/Ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.sohu.com/Ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://mirrors.sohu.com/Ubuntu/ lucid-updates universe main multiverse restricted
网易开源镜像站,提供FreeBSD，OpenBSD，archlinux，centos，cygwin，debian，Fedora，gentoo，kernel，openSUSE，slackware，Ubuntu
deb http://Ubuntu.cn99.com/ubuntu/ lucid main universe restricted multiverse
deb-src http://Ubuntu.cn99.com/ubuntu/ lucid main universe restricted multiverse
deb http://Ubuntu.cn99.com/ubuntu/ lucid-security universe main multiverse restricted
deb-src http://Ubuntu.cn99.com/ubuntu/ lucid-security universe main multiverse restricted
deb http://Ubuntu.cn99.com/ubuntu/ lucid-updates universe main multiverse restricted
deb http://Ubuntu.cn99.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb-src http://Ubuntu.cn99.com/ubuntu/ lucid-proposed universe main multiverse restricted
deb http://Ubuntu.cn99.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://Ubuntu.cn99.com/ubuntu/ lucid-backports universe main multiverse restricted
deb-src http://Ubuntu.cn99.com/ubuntu/ lucid-
updates universe main multiverse restricted
骨头源，提供Ubuntu,deepin
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
sudo aptitude update #更新列表
sudo aptitude upgrade #更新系统