1,最好用系统自带的apt源,我用163的源升级没有成功 tao@tao-desktop:~$ grep -v ^# /etc/apt/sources.list|grep -v ^$ deb http://cn.archive.ubuntu.com/ubuntu/ precise main restricted deb-src http://cn.archive.ubuntu.com/ubuntu/ precise main restricted deb http://cn.archive.ubuntu.com/ubuntu/ precise-updates main restricted deb-src http://cn.archive.ubuntu.com/ubuntu/ precise-updates main restricted deb http://cn.archive.ubuntu.com/ubuntu/ precise universe deb-src http://cn.archive.ubuntu.com/ubuntu/ precise universe deb http://cn.archive.ubuntu.com/ubuntu/ precise-updates universe deb-src http://cn.archive.ubuntu.com/ubuntu/ precise-updates universe deb http://cn.archive.ubuntu.com/ubuntu/ precise multiverse deb-src http://cn.archive.ubuntu.com/ubuntu/ precise multiverse deb http://cn.archive.ubuntu.com/ubuntu/ precise-updates multiverse deb-src http://cn.archive.ubuntu.com/ubuntu/ precise-updates multiverse deb http://security.ubuntu.com/ubuntu precise-security main restricted deb-src http://security.ubuntu.com/ubuntu precise-security main restricted deb http://security.ubuntu.com/ubuntu precise-security universe deb-src http://security.ubuntu.com/ubuntu precise-security universe deb http://security.ubuntu.com/ubuntu precise-security multiverse deb-src http://security.ubuntu.com/ubuntu precise-security multiverse deb http://archive.canonical.com/ precise partner 2,开始更新 tao@tao-desktop:~$ sudo update-manager -d 弹出更新管理器,发现有新的版本12.04LTS,双击升级即可