sources.list問題重新安裝Ubuntu12.04放棄Ununtu14.10，開始安裝Ubuntu14.10版本，無論怎麼修改/etc/apt/sources.list，在安裝軟體時都找不到package

所以重新安裝Ubuntu12.04 Precise 的32位Server版和32位Desktop版本。

1 下載安裝Ubuntu12.04 Precise映象

下載地址：http://releases.ubuntu.com/precise/

2 在vmware12 中安裝Server版

安裝見：

3 更新sources.list源，否則有些包無法定位

（1）注意1 先備份舊的的sources.list

$sudo cp /etc/apt/sourcs.list /etc/apt/sources_original.bak

（2）編輯新增國內比較快速穩定的源，注意新增的源中用的版本名要與Ubuntu版本要一致，否則災難不斷，Ubuntu12.04的版本名“Precise”

$sudo vi /etc/apt/sources.list

在檔案靠前加入下面的一個或者幾個源，儲存退出。

（3）馬上更新源

$sudo apt-get update

附推薦的“Precise”更新源：

<span class="preprocessor" style="color: rgb(153, 153, 153); font-weight: bold;">##網易源(廣東電信：適合電信使用者)</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-security main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-updates main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-proposed main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-backports main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-security main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-updates main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-proposed main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.163.com/ubuntu/ precise-backports main restricted universe multiverse</span>
 
<span class="preprocessor" style="color: rgb(153, 153, 153); font-weight: bold;">##搜狐源(山東網通：適合網通使用者)</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-security main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-updates main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-proposed main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-backports main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-security main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-updates main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-proposed main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirrors.sohu.com/ubuntu/ precise-backports main restricted universe multiverse</span>
 
<span class="preprocessor" style="color: rgb(153, 153, 153); font-weight: bold;">##臺灣ubuntu官網源</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-security main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-updates main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-backports main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-proposed main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-security main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-updates main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-backports main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//tw.archive.ubuntu.com/ubuntu precise-proposed main restricted universe multiverse</span>
 
<span class="preprocessor" style="color: rgb(153, 153, 153); font-weight: bold;">##教育網帝都的可以使用北理工的源</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-security main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-updates main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-backports main restricted universe multiverse</span>
deb http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-security main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-updates main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-backports main restricted universe multiverse</span>
deb-src http:<span class="comment" style="color: rgb(153, 153, 136); font-style: italic;">//mirror.bit.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse</span>