root@xxx:/opt# apt install unzip Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package unzip
出现上面问题，执行下面命令后就可以
root@xxx:~# sudo apt-get update sudo: unable to resolve host iZ2zeavqe88suzfdrbj5q6Z Hit:1 http://mirrors.cloud.aliyuncs.com/ubuntu xenial InRelease Hit:2 http://mirrors.cloud.aliyuncs.com/ubuntu xenial-updates InRelease Hit:3 http://mirrors.cloud.aliyuncs.com/ubuntu xenial-security InRelease Reading package lists... Doneupdate 是同步 /etc/apt/sources.list 和 /etc/apt/sources.list.d 中列出的源的索引，这样才能获取到最新的软件包。
