Ubuntu 下获得root 用户 + 14.04源
Ubuntu下获得root 用户：
sudo passwd root
Enter new UNIX password: (在这输入你的密码）
Retype new UNIX password: (确定你输入的密码）
passwd: password updated successfully
以后，如果在想获得root权限，只需进行如下的操作：
su root
Password: (在此输入你上面设置的密码）
如果要再次禁用 root 帐号，
那么可以执行 sudo passwd -l root
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Ubuntu 14.04 的源：
1. 备份源：sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
2. 编辑源：sudo gedit /etc/apt/sources.list
3. 更新源：sudo apt-get update
163源:
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deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
搜狐源:
deb http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse
oschina源:
deb http://mirrors.oschina.net/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.oschina.net/ubuntu/ trusty-backports main restricted universe multiverse
deb http://mirrors.oschina.net/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.oschina.net/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.oschina.net/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.oschina.net/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.oschina.net/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.oschina.net/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.oschina.net/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.oschina.net/ubuntu/ trusty-updates main restricted universe multiverse
from http://my.oschina.net/zhangrf/blog/224661
以备不时之需
