安装landscape-common，可以在登录时候显示一些基础的信息，例如CPU内存占用等等
sudo apt-get install landscape-common
安装update-notifier-common，当有软件包更新的时候，会在SSH登录成功后提示用户
sudo apt-get install update-notifier-common
效果如下：
Welcome to Ubuntu 16.04.2 LTS (GNU/Linux 4.4.0-74-generic x86_64) * Documentation: https://help.ubuntu.com * Management: https://landscape.canonical.com * Support: https://ubuntu.com/advantage System information as of Mon Apr 24 11:20:30 CST 2017 System load: 0.08 Users logged in: 0 Usage of /: 44.2% of 39.25GB IP address for eth0: X.X.X.X Memory usage: 80% IP address for eth1: X.X.X.X Swap usage: 0% IP address for docker0: X.X.X.X Processes: 109 Graph this data and manage this system at: https://landscape.canonical.com/ 8 packages can be updated. 0 updates are security updates. Welcome to aliyun Elastic Compute Service!