近日做项目，遇到自己的ubuntu版本太低，加之网速比较慢，实在是很无奈，只能更新下数据源。
在更新数据源之前的，你必须做点工作:
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak #备份 sudo vim /etc/apt/sources.list #修改 sudo apt-get update #更新列表以下是阿里云的更新源，相对比较好：
deb http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse