ECS的Ubuntu下载时Reading package lists... Done Building dependency
在ECS的Ubuntu下载时出现Reading package lists... Done Building dependency
一般apt-get出现这种情况：
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package ****
就是没有更新APT库
更新一下就好了
sudo apt-get update
sudo apt-get upgrade