[ERROR] media change please insert the disc labeled

开始用ubuntu server, sudo apt-get install openssh-server时遇到的问题，报错：

   media change please insert the disc labeled

解决办法：

sudo vi /etc/apt/sources.list
注释 deb cdrom那一行
sudo apt-get update && upgrade
sudo apt-get install openssh-server

参考：

https://blog.csdn.net/genius_zz/article/details/52563309