ubuntu 14.04安装
最近想搞spark。没有集群环境，想先在单机上跑。但是两年前一直用到现在的virtualbox已经太老，很多源都停更了。所以准备装ubuntu14.04。
0. 更新源。163的源有问题，用的是sohu的源；
1 deb http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse 2 deb http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse 3 deb http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse 4 deb http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse 5 deb http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse 6 deb-src http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse 7 deb-src http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse 8 deb-src http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse 9 deb-src http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse 10 deb-src http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse
然后执行：
1 apt-get update
1. 首先是允许root登录；
1 vi /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf
加入这一句：
1 greeter-show-manual-login=true
然后再修改一下root密码：
1 sudo passwd root
2. 装virtualbox 的extension，不然都不能全屏和复制；
老是提示
The headers for the current running kernel were not found. If the following
module compilation fails then this could be the reason.
解决方案是安装下面的东西：
1 apt-get install g++ linux-headers-3.13.0-32-generic build-essential dkms
缺一不可。
